I play mostly by feel when it comes to club selection and I play a lot of shots that people would think are "weird", for instance I might hit an easy low punch 4 iron into a 150ish yard par 3 hole that has no front trouble but the pin is back on a deep green. You probably don't want to watch which clubs I hit out on the course, I've screwed up more than a few people who have.
I do have a pretty good idea how far I hit everything in the bag though. My GPS has come in very handy this year as I've been playing new irons (twice) and needed to measure a few shots to get the distances dialed in. I end up measuring at least 4 or 5 shots almost every round even if I don't use the GPS for much more than basic yardages. It's a handy device for things like that.
WBL posted in another thread about the range being useless for ranging your clubs and I agree 100% with that. The best way is to go by what you actually hit out on the course with the balls you regularly play.