Q: How do I redeem 'Mech Performance Steam Pack?
In order to redeem Steam Performance Packs, you need to download the MWO client through the Steam store.
Once this has been completed, launch MWO through your Steam library and login to your MWO account as you usually do for your independent client. Upon this login, the Performance Pack(s) will be redeemed on your account.
Once these have been redeemed, you can uninstall the Steam client if you don't wish to have two separate MWO clients on your PC.