I've been using 1st less and less, I could live without but I'm sure by clutch and wallet are happy about it. I only really use it from an uphill stop, in stop and go traffic and for snappy launches. 2nd does a better job if I'm starting up into a turn, starting from a roll or on a level/ downhill road.
I've found that I get better results when I don't downshift unless I'm going to bog the engine (in 6th 50-70). The car seems to have more passing power when I stay in gear (ie 3rd gear around 35mph) and let the gear see the whole RPM range, theres a little more area under the acceleration curve.
I'm considering using an SRT rear with its numerically lower gear ratio, I think I would be happier with it.