You should be looking for 1.21+ and IR under 2.0 for good 4200's. Low IR is just as important if not more important to high voltage for stock racing as this will effect the punch out of the corners. You may want to check out the EP4200 as well. They have been proving to be pretty amazing batteries.
A couple top matchers are starting to carry the EP cells.
TLR/Losi Team Driver
TLR/Losi | Tekin | Venom | DE Racing | Spektrum | Exotek | JBRL | Kolor Koncepts | OC/RC |Sticky Kicks | Imagine It Graphics | Casper-RC.com
TLR 22 3.0, TLR 22SCT 2.0, TLR 22-4 2.0, TLR Ten-SCTE 3.0, Spektrum DX6R
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