they burn oil by design. it lubricates the tips. if u want them to really run well, put abit of 2stroke oil in the fuel.
ive never owned an rx8 but i have owned rx7s and they are brilliant, im sure the 8 would be as good.its is seriously important that u warm them up, u can do alot to them and they will take it, and if u do need a rebuild its alot cheaper than rebuilding a YB for sure.
they look good.
ive driven a 350z and thought it was abit crap tbh, the noise wasnt good and it wassnt very exciting, it was only getting about 22mpg aswel and ive read that rx8s are meant to get about 25.