I'll admit that when I first started out playing 40K -- and Space Marines in particular -- I was a bit put off by the idea of the "Standard Template Construct". I thought it was a very, very cheesy way for GW to cheap out on making different models for SM tanks, transports, etc. I don't love the idea that my "battle tank" (the Predator) looks like my transport options (Rhino or Razorback).
However...I did learn to love it today...or at least, hate it less.
Because I decided that for the upcoming Escalation game, I didn't want to use the Predator I have under construction, but that a Razorback would be just the thing. So all I'm going to have to do is glue on the RB parts to the already-completed Predator chassis and presto, instant Razorback.
So while I'm still not happy about the whole STC concept -- I'd rather my tanks look like tanks, damn it, not like transports with turrets and/or sponsons -- I have to admit it made my life a lot easier today.