Some have found that the Maxamps 3000mah cells (that are in the 6000HV packs) aren't all that great... However, the Maxamps 5000mah cells have been awesome in my experience with them. You could get a 4s1p 5000HV pack, and run it with a 7/8/9XL.
http://maxamps.com/proddetail.php?pr...-5000-148-Pack
And, the 4s1p 5000HV pack is $25 cheaper than the 4s2p 6000HV pack and 140grams lighter.
SH Z-Car, Custom Crawler, 8s Savage,
12s XTM XLB 1/7 buggy,
4wd 4-link rear/IFS Pro4 truck,
Custom Hyper 10 Short Course,
Belt-Drive Mammoth ST 1/8 truggy, 4s 17.5 MM Pro HPI Blitz