Those should be just fine. I used a TrakPower LiPo on mine with HV servos but you will need a LiFe pack or a regular NiMh flat pack. This one is about the same size as the TrackPower LiPo I ran, Flat LiFe pack, so I know it fits. The specs on those servos are very similar to the Sanwa SRG-BLS V2 I used and never had any issues with steering or brakes. I don't know what kind of budget your working with but in my opinion those servos with a Legend 12R will get you a nice performing setup, although it's out of stock there.