Understand that their base HP is the wrongly advertised 330 HP (349 actual), so the gains aren't exactly accurate. Also, different dynos register different outputs. Mustang dynos are widely regarded as the "heartbreaker", usually giving you the lowest numbers. I'm still running a 65 for the reasons you mentioned.....I don't want to upgrade injectors. Already installed them on Thumper's car and it's a pain in the @$$. The 62 can normally deal with just an SL55 fuel pump unless you're down at sea level like me. If you plan on riding at WOT for extended lengths, get injectors and a dyno tune.