Lipo's for the FLUX

I have been reading a lot and am still kind of lost on what to get. I have a flux that should be here today and I am looking at what lipo I should buy. I have two thoughts I would like feedback on if you can help. The first is speed I would like to have speed. I have a brushless traxxas slash with an 11.1V 5000 Maxamp and it has too much speed. So I am looking to get around 50MPH and good runtime. Out of the list below what would you go with and why. Money is a concern but not at the cost of the ESC. Thanks for you help
Best Regards,

7.4V

ER
5100 2s 25/50 90.00 180.00
5000 2s 30/60 110.00 220.00
TP
4200 2s 40/80 100.00 200.00
5000 2s 40/80 125.00 250.00
LS
5000 2s 20/30 96.00 192.00
PQ
6000 2s 25/40 128.00 256.00



11.1V
PQ
3000 3s 30/60 70.50 141.00
2400 3s 25/50 60.00 120.00
2200 3s 20/30 54.00 108.00
6000 3s 25/40 154.00 308.00
TP
5000 3s 40/80 190.00 380.00
4200 3s 40/80 150.00 300.00
3200 3s 40/80 130.00 260.00
LS
5000 3s 20/30 135.00 270.00