I road my 350 about 40-50 miles of single track, and same mileage on FS type roads last weekend. Same blackdog DS route I road with my wrr last year. The 350 power and suspension jump right out as the biggest advantages. Felt a lot more solid and stable at speed on the rutted and rocky sections. The bike can just flat out blast on technical terrain. It wants to go faster as the conditions get worse. Although the wrr does well, there really is no comparison when riding the real nasty stuff. Also nice to be able to blip the throttle and loft the front wheel over a tree or water filled hole, etc. I geared mine at 14/48 w/116 link chain (stock is 15/45, 114 links), which still felt a bit tall for the tight single track. Found myself going into 1st in some sections, would prefer to stay in 2nd. But this gearing felt about right for the FS roads. This is compromise gearing...
Comfort? Like all previous years with KTM, a seat upgrade is a must do mod. I installed the seatconcepts kit with carbon fiber fabric top and sides, it's much more comfortable (and cheaper) than the Renazco on my wrr. Although, looks wise the Renazco really is a work of art. Also the engine vibs are more noticeable on the 350 as your riding roads, so comfort wise not as good as the wrr.
For now, I'm still keeping my little wrr as a reliable, no fuss, long mileage bike. Different mission statement than the 350. I will not hesitate taking the wrr on a 7+ day multi-state off-road tour. The jury is still out as to the reliability of 350. Soon as the snow melts off in the north cascades, I'm going to put the 350 to a test with a 1000mi wbdr ride. It's close to home so much less risky than a TAT ride thru NV. I did this same route last year on wrr so will be interesting to compare.
Here's some pics to ponder w/many adv type mods. Acerbis just released their 5.1gal tank, but I may wait till the Safari 15L comes out this summer to install the bigger tank.
all hdb and sicass in the cockpit, with scotts submount
installed bright 5w led headlight bulb into factory receiver to save on stator output