I bought my Easywalker as a direct result of seeing the poor workmanship and finish on the Mountain Buggy Duet. Mine was simply awful - threads that hadn't caught, threads that needed cutting off, pink foam sticking out, rough rivets, messy stitching, a lck that wouldn't undo / lock easily, a possibly twisted chassis, lcking hoods, the hole in the hood, a bumper bar that kept falling off and more. However the +One is very good apart from the small D rings and it's restored my faith a bit in MB products. But the Easywalkers seem to be very sturdy, good quality more canvas type fabrics and I can't fault the two Easywalkers that I have had apart from the sun visor on the double. But I also do not do serious off roading - the beach, lake, park and unmade bumpy pot holey roads is the best we get. I don't know about the wheels at all on MBs.
Certainly the older MBs have the green one hill tree logo (as on the left of the advert) and as someone said, no bumper bars. I would say those are new Chinese MBs.
The one thing which you have kept saying is re taking the pushchair on a bus folded. There's no way I woud a) want to fold the MB on a street to get on a bus. You need to remove the child, fold two handed from the front, then run round the back and do the easy but fiddly clip up to hold it all together. Then the MB will stand on its end but they all have tall, long folds. I wouldn't like to carry it onto a bus either. I took a photo of DD by the +One box because it was way taller than she is. The Easywalker Qtro, and the Duo (I can't look the Sky up without losing this) folded very neatly, easily and compactly. The Duo has one of the best double folds. The Qtro has a lock too. I could easily do that probably even holding my child's hand (even though it's two handed) stood up rather than the bending down to the floor you need to do for the MB.
Personally I think you get more for your money with the Easywalkers. I love the quality of the Easywalkers. The attention to detail is far better than the MBs eg the recline, storage, footplate. I know the MBs are made of I think steel and aeroplane grade aluminium, but I also know the frames do get twisted (and untwisted). I don't know about the Easywalkers. All I know is that getting the Qtro after the Duet restored my faith that there were good quality products on the market and the Duet was a one off lemon.