I chose the ebay unit because of the price. I knew about what size compressor I needed and after doing some research about turbine A/R I decided that the 1.05 would work but be laggy off idle. I was shooting for something in the .80-.90 a/r range but for my initial build most of my choices were out of my budget. I figured I could get it running and upgrade when I have the cash. I wasn't concerned about all out track performance because it is mainly street driven.

Side note: After alittle bit of tuning today I realized that the 3.55's are kinda steep with the 904's first gear. It revs too fast and your going to second too soon. I may try the 2.94's I have but I'm going to wait until I swap to a glide before I change the rear gear