Car parts add up quick and if you do plan on ordering parts over time, Tier 3 will save you the most money and also offers the most benefits.  If you plan on ordering occasionally, Tier 2 is recommend for the extra % discount and extra entry into the VIP Giveaways.   Tier 1 is if you only want basic benefits, like access to VIP Prices.  Fact: 30% of our members have upgraded to Tier 3.