You guys do realize that the leaving a spring compressed myth was disproven, multiple times, on both Arnies, ASR, and Airsoft Mechanics right? Quality springs will not lose FPS beyond the initial "bedding in" if left compressed. One of the guys on Arnies left a set of random stock springs fully compressed for something like 6 months using bolts, nuts and washers and popped em in a gun and saw no difference in FPS before or after.
Is it good on the rest of the internal componenets, most definetly not.