Yamaha and Honda has the best resale value. Problem is that this CBU big bikes are parallel imported - but I believe there are plans for both Yamaha and Honda to bring this bikes in.

People say that Suzuki is rank the lowest in resale value for big bikes when you line the big 4 japanese makers together. Honestly, I find that perhaps not many people are favourable of Suzuki big bikes. Personally, I really like the looks of the K9 GSXR 750 & 1000.

As for parts availability - I only own Kawasaki bikes and its my 2nd bike now. Cant say if it is a fool proof method to get parts for the other makers. But most people would say this shop has it, that shop has it and etc etc.