Both are good motors and are easy to upgrade. You can find replacement parts for both easily "its not 2004 anymore ppl you can get RB parts anywhere". It really comes down to how much $$$ you have and or willing to spend. If you got $$$ do RB it docent mess up the cars balance "not that ppl care about that around here anyway" and it can handle up to 500 on stock bottom end but i personally wouldint. If you dont have $$$ to burn just use the VQ and turbo/supercharge it.