I get such question pretty often. Especialy because I am 185 cm tall which is far enough for dual 26″ bike. The answer is a bit longer as it describes my recumbent experience which is couple of years long. I started to ride recumbents sometime around 2003. In that time we were working on a very first prototype of AZUB TWIN recumbent tandem and I planned to ride it from Czech Republic to Athens and back, to see the Olympic games. The TWIN is 20/26“ recumbent with a bit higher seat height than is common for such configuration. All was quite OK, I felt very safe and could steer it also in very slow speeds. But there were the legs of stoker which I could „use“ when in difficult conditions.
Than we started to plan a trip to Albania and other Western Balkan countries with my wife and it was clear we cannot ride on tandem there. Especialy becuase we wanted to visit remoted places deep in mountains where there are very bad roads. Roads which seemed to be unridable on a recumbent. At least all who were there told us so. In my eyes the only bike which could manage that was the MAX, or better to say the model which we called HardCore in that time. Dual 26“ wheels, full suspension, under seat steering. We built two extreme bikes and went to Montenegro to see what will happen.
Albania is all up and down. You can hardly find any falt roads there. Maybe somewhere around the coastline you can find some. The rest are just beautiful mountains with steep and often rocky roads. We could ride almost everything and I was quite proud what everything we cycled there, but I felt down many times too. Not in high speeds going downhill. Usualy in very slow speeds going uphill when there were very difficult conditions.
I do not like to give up, so I always rode as further as possible. I let the bike danced under me, I balanced and tried to go. But when the rear wheel lose adhesion, I had to stop. That meant I had to put my feet down to touch the ground, but it was too far away from the bottom bracket. Usualy if I managed to have enough fast foot, I put it too close to the bike and I could not hold all the weight of myself and luggages on top of the carrier and so I fell down. In case I managed to have enough fast foot it was often pretty difficult to get off the bike as it was leaned backward, the centre of gravity was high, the gravel was slippery etc. This was not fun.
The experience was the same also the next time when I was in Albania guiding a tour of mountain bike riders. I was there with the MAX again, but without luggages. It was much better in difficult conditions, but still there were places where I fell down couple of times. The third time I went there to ride almost the same route as before (these times I have been at least once a year there as a guide of travel agency) I took a MINI. Whooh! What a change! With good front frok and rear suspension and with proper tyres, I could ride almost everything. With no falls at all. Well, maybe one or two during 10 days. Yes, I had to care much more about deep holes, but all the rest was just pure fun.
And why? Because I was much lower. I had much better feeling, I felt more safe and I was bolder. And the key factor was the seat height.
Later I had to decide for my only one personal bike. Bike for everything. For 24 hour races, for rides in terrain, for long distance touring. So I decided for AZUB Mini with above seat steering.
Because it is narrow so I can easily store it in basement where the door is pretty narrow too. I can also easily load it into the train or have it in the car or pack it for flying. Also the ASS is virtualy undestructible. And I realized later in Himalayas, that I can also quite easily ride it in terrain too although I thought it will be more difficult with ASS than USS.
I think that the best bike for terrains and long distance cycling is probably the AZUB 5 with 20/26“ wheels because the rear derailleur is not that low above the ground and also you one can choose from wider range of tyres, but I like the look of the Mini, my wife often ride trike with all 20“ wheels and soon we will ride with children trailer which also have 20“ wheels. That means one 26“ wheel it would be more tyres and tubes which doesn’t make sense. Also the sitting position is more sporty on the MINI as same as on the MAX which I like more.
If you plan to ride only in the terrain, the best choice would be the MAX with 24“ wheels. This is an experience of couple of our customers which changed wheels on the AZUB MAX from 26 to 24“ wheels. They often kept the 26“ front fork to have it high quality as 24“ forks doesn’t exist in good quality in fact.