Most discussions on the topic does not consider the fact that the right choice between hard or soft luggage varies from person to person and the bike/luggage combo. So, before asking the question, which is best, I will shed some light on the specifics in my case.
Some 20+ years ago I left soft bags in favor of aluminium panniers, and I have never looked back. Now I am up against some decisions that are making me rethink it all.
The number one thing I came to love about hard panniers in the first place was that I had a greater peace of mind leaving my luggage unattended, even if just for a few minutes at a boarder, on a ferry or jumping in and out of stores. Although still fairly easily broken into, it didn't make criminals out of ordinarily law abiding citizens.
The second greatest thing was the ease I could load and unload my gear at the beginngin/end of every day's ride - simply pull out the inner bag and go. No more hassle routing, doing and undoing straps, aligning bags, etc, etc.
There were other benefits as well, though not as important to me - i.e. the ease of access of all its contents throughout the day, or being able to use the panniers as a seat and table, or being able to use it as a make shift jack stand, or covering it with country flag stickers, or the ease of which I could strap down other gear on top of the panniers.
The number one draw back of hard panniers in my opinion is weight, girth, weight distribution and to some degree also the potential for personal injury when eating dirt. However, this has until now never really never been a major issue for me. The bikes I've used allways have been a bit fat in the first place. My last being a BMW F650GS Dakar (176 kg dry, eks farkles). Further still, even if I have allways been stringent on what to bring, my trips have often been such that the constraints of region/time/distance has forced me to bring lots of tools, spares and equipment - adding tons of weight. Lastly, I don't ride very fast or hard when off road anyways... slow and easy does it for me. In other words, the realtive difference the lower weight of soft bags has offerred has so far had little impact.
The question for me now is if what I am planning now will make me want to change out hard panniers for soft?
I am now in the process of planning a new adventure bike. I'm conscidering the Husqvarna 701 Enduro (based on the discontinued KTM 690 Enduro), weighing in at only 145 kgs and 50% more power than the Dakar.
The bike does not have a sub frame (the tank is the sub frame), but it is strong enough to carry a pinion. I believe that it does not need to have its sub frame strengthened to any significant degree for soft bags. I do however believe that hard panniers would require sigificant strengtening of the sub frame.
The main reason I am considering this bike is its low weight. For this reason I would be very careful about adding any farkles that would diminish this winning attribute. I would add fairings and hand protectors to keep me out of the elements, maybe a bash plate and grill protector, maybe a an auxilary tank, strengthen a few known weaknesses, change the exhaust to reduce weight even more, and if uncomfortable - change the seat. That would be just about it for mods that would affect weight. The added weight from mods would be close to nothing in the greater schemes of things. The greatest difference would come from choice of luggage.
As my next adventures will not be put under such extreme time/distance constraints as previous adventures, I will no longer need to carry as much "monster insurance" in the form of spares, tools, and gear. I've allways preferred to keep it as lean as possible, if not only to reduce clutter in my life. I like only to bring what I really need, which won't be much when I have more time on my side than before.
I am a true believer that any bike/gear combo is capable (not suitable) to get you anywhere on this planet (I have participated and completeted the longest African enduro rally on a classic Vespa PX200E Vespa, unassisted, just to prove the point (7000+ kms/3 weeks). The point here being that even though any bike/luggage combo will get me where I want to go just fine, I am looking for a "best solution" answer. I am no longer about to prove that anything is "capable". I am now reired from those sort of trials. I now only want the most "suitable" for my intents and purposes - I want comfort and peace of mind! My question to you is therfore not what will work well, but rather what you think will work the absolute best for me - is this the secure hard panniers with all the added weight or the light and soft panniers???
Like I said, the sense of security from hard panniers vs low weight is a difficult tradeoff for me. I am also a creature of habit, so I will need some convincing to switch to soft if that is your advice.
The way I see it. Although one can argue that many soft bags are harder to get into than they look - the novice thief might not know that. They may try to cut it off or cut into it thinking that whatever is bulging inside might be of value. Even if they are unsuccessful, their attempt could still truely ruin my day. I also believe that a bulging fabric bag, that clearly has contents inside, invites the attention of thieves. The hard panniers on the other hand can be presumed empty if nothing else is left on the bike - not evoking any further desire to neither investigate or get into it.
My choice will boil down to which alternative will provide me with the greatest "comfort". I am a true believer that one of the highest priorities when kitting for an adventure should be namely "comfort" aspects (rideability, riding comfort, riding style, a good night's sleep, a cold

, reducing clutter, serviceability, reliability, etc, etc).
I believe that comforts, on and off the bike, makes for an alert and energized rider - one that makes fewer mistakes that could result in injury or mechanical failure. I also believe that "comforts" allows more attention to the pleasures of the trip rather than having to put an abundant ammount of energy on keeping oneself upright and going forward.
I see that the light weight soft luggage is a creature comfort when the wheels are turning, but a pain in the ass when they are not... and vice versa for hard lugage. I'm wondering how much more apparant this difference will be when riding on a lighter bike with less stuff in the luggage? Question here is which comfort to sacrifice?
Now that you know more about my riding style, choice of bike, my concenrs for security, etc, etc. What do you think would be the best option for me?
Please let me know what type of lugage that you have used, what you are using now, the reasons why. If you plan on switching... why? Have you had your luggage stolen or broken into?
On a final note. My top contender for hard panniers is Touratech. For soft, it is Green Chile (basically only a strapping system where I can strap down any type of bag, firewood, x-mas tree, groceries, crates of

, tent, or deer....
https://greenchileadv.com/
An important insight is that my trips can take me anywhere from cities to the outback, in the most developed countries or the least developed countries - and often in the same trip. Sometimes I travel in groups, sometimes alone. In other words, I need an all purpose set up.
Any opinions or insights will be greatly appreciated.