Is there a major improvement or difference between the two? I was at the local GS today and they only had the 30 and I liked it. How much different is the SF? I dont know if I should buy the 30 or wait til I get my hands on a SF before I pull the purchase. What say you? 
and are the G30 mags compatible with the G30SF?
I have a 21 and a 21SF. There is a significate diff for me on the trigger reach.
I also have a 30. I have tried the 30 SF but the org 30 fits fine. Go figure. I carry the 30 and love it. The reach to the trigger is OK. I plan on selling 21 and keepin the 21 SF because of trigger reach. You are going to have to try each to determine for yourself. Every hand is different