I finally got around to installing a TransGo shift kit in my 05 GTP. I installed the kit to help with a sluggish 4-3 downshift problem. All the shits are quicker and less noticeable. My 4-3 downshift under a load (mountain driving) is still somewhat harsh, but only about half as severe as it was. It's manageable now. All the other shifts were improved. All shifts are quicker without slamming or banging into gear. This kit won't cause the hard shifts that break components or mounts. For a low price, this upgrade is worth the money and is very streetable.