I had to buy 15" wheels for the pioneer, and now run a 35" tall tire with no issues at all. For the extra maintenance of the portals, it is just changing the oil. The portal is just a gear reduction box at each tire. I think you need to change the fluid at 30-50 miles for the break in and then every 'X' number of miles depending upon your riding style. I change the fluids in my every 600 miles for my type of riding after taking to SATV and only use portal blood from SATV, but I ride out in the desert and woods so I'm not submerging them in water and mud like others. Takes 45 min to change the fluid, the hardest part is removing the wheels to get to the portal.
I would do it again and have no regrets.