Ok my turn to post my experience.
Studied casually for about 2.5 weeks about a year ago. Kaplan / PR. Diagnostics on PR 680.
One year later, took Kaplan 1 month course. Diagnostics 680 (pretty darn consistent!) However, missed Verbal lesson #2 & #3.
Did most of exercise and Kaplan paper test. Scores as follows:
Paper test: 690, 690, 700, 750, 720, 660
CD ROM: 630, 620, 600 (got completely freaked out that my score was going down!)
PowerPrep: 660, 720(49q 40v)
After about 1.5 month of intense study (30 questions of Q and V a day, intensifying to 1 test a day during last 1.5 weeks, to 2 tests a day couple days before exam)
Walked into test center all nervous. Got freaked by the first math question... my brain froze! There are some real tough ones out there!
During verbal section desperately tired. Haven't eaten all day so exhausted by 15th question. Got through...
I originally aimed for 720 but 730 it is! No more GMAT!!! For all those there I know how it feels. Good luck to you all!