The age old fight between YS and Saito..... Compare prices YS 110 to Saito 150, YS 63 to Saito 90, YS 140 to Saito 200.... thats also the power comparison. Also if you assemble your tank as per mfgr with 1 fuel line and 1 press line, you should not have a tank problem. The only thing added is a T in each line for fueling and press release.
Saito's are great motors and YS's are Awesome so either way, you cant go wrong.