Real GMAT: 660 (Q47, V35) SO FRUSRTATED!!! :( :( :(
(Actually, got so nervous that slept for only 1,5 hrs the night before the test and had 3 coffees to keep me awake during the test. So, had a problem concentrating.)
PowerPrep: 610 (Q42, V32), 770 (Q49, V48)
Kaplan: 620, 670
Crack-GMAT: 555 (Q34, V23), 670 (Q49, V31), 520 (Q36, V14), 680 (Q49, V33), 670 (Q52, V28)
800score: all above 680. Actually, the quantitative sections are SO EASY that they are no use for any serious practice.
In my opinion, the best practice tests to take are those in PowerPrep and Crack-GMAT. Unlike Kaplan, Crack-GMAT has 5 really distinct tests with not a single question repeating from test to test. Also, the quantitative section in Crack-GMAT has really good examples. So don't miss this one!