Revs hanging is sign of an airleak. I'll tell you man my build was on a tight budget. Family of 5 and I don't make as much as I should or would like. I wanted to do just the minimum to get mine up and running. $3k later i have the piece of mind, and knowledge (from here), to know its gonna run good for a long time. As I think Blaasters sig used to say, Never enough money to do it right the first time, but always enough to rebuild, or something like that. I started on ebay and paid for most of mine through that, 90% of what I sold I had and didn't need/use or got from other people for free. It was a pita but paid for my build. It is always worth it to do things right the first time, or you pay for it later, or maybe sooner.