I just picked this harness up 10 days ago, and cored my first ever thermal using it last weekend. Coming from the Altirando 3 and Radical 3, this harness is definitely super comfortable for long flights and stable in turbulence. I'm glad you mentioned the way the seat-board sits when kiting, because that was a huge bother in the Altirando 3. With the Altirando Lite 2, I barely notice the seat-board and reserve when kiting! It's my preferred hike-and-fly harness right now!
I can confirm everything you said. Just got this as my first harness around 3 weeks ago and of course, as a beginner, I haven't flown a lot of other harnesses but I can say that personally, I couldn't think of anything better.
Great to hear! Having tested the Altirando Lite 2 for several months, and gotten to know it really well on the ground and in the air, I expect you'll like it even more with time. How do you find getting in and out, following the tips we give in this video?
As you can see in this video, the airbag of the Altirando Lite 2 pre-inflates exceptionally well - giving full protection very quickly, if not immediately - and seems to offer excellent protection, both under your bum and right up your back - which is better than most, and far better than some - so we at Flybubble rate it very highly.
I feel the airbag of the Altirando Lite 2 is exceptionally well designed in that a) it is totally separate from the rear storage (so no worries about the gear you put in the back stopping the airbag from inflating, especially since you can zip up the backpack part within the rear storage to keep it totally separate and close to your back), b) in flight mode the part of the airbag that goes up your back is a separate compartment, a double-skin, and c) the whole airbag section is within the backpack when in backpack mode, not exposed. With many reversible harnesses the backpack is the airbag which means if the backpack gets damaged/punctured then the airbag is damaged/punctured. With the Altirando Lite 2 this is not the case, the backpack is totally separate from the airbag (and even removeable from the harness).
I've not tried it but I guess it might be possible for airlines with more generous carry on luggage size allowances (not stingy ones like Ryan Air). Generally to be more sure I'd recommend the more compact Mountain Paragliding Harnesses ( flybubble.com/harnesses/mountain-paragliding-harnesses ) either with their dedicated reversible backpack if they have one (could be integrated, could be an add-on) or a well-matched ultralight Paragliding Backpack ( flybubble.com/bags/paragliding-backpacks ).