drop spindles?

[zigs74]

Ik this has been covered a lot but I would like a little more input between which size spindles & springs. I'm currently looking at Bell Tech 3" spindles & 1" springs with a coil cut for five" drop? Also what if I did 2.5 spindles 2" springs 4.5 drop? Would there be much of a difference in ride or rubbing? A 6" drop flip kit & plan on using the stock 15" rallies for quite some time. I like the way they look but maybe plan on putting 20's in the future. One last ?, What could I expect to pay for the labor? Thx evy1!