xr400
I have ridden my xr 400 off road and on a variety of easy and challenging trails. It performs pretty well overall, and we have got to know each others weaknesses pretty well after 3 years.... however, IF you stall it, by falling off for example, it is an absolute b*****d to start as it floods very easily! Also, if you tackle a steep technical track and "run out of momentum", (i.e. stall it or fall off!), then you often have little choice but to turn around , go back down and start again, thats assuming you can turn it around! So, it does make you think very carefully about some trails where those lucky blighters with magic button would not think twice but give it a go! In addition, you can get very very knackered kicking it over, and if you fall off a lot (who, me? thats coz I am trying very hard!) then you can run out of steam very easily by the end of a good days off roading!
If I had the choice , I would go for aDRZ "e" and add the road kit, yes they are noisy but never, ever underestimate the value of that magicbutton!
hope that helps, happy trail riding!