First off, Orions have a very good quality reputation, lots of fast guys use them, so yeah, it's a good battery.

The C value is a good indication of the ability to deliver punch. Basically C is the current that it takes to discharge in 1 hour. So in your case the 1C rate for your 4800mah battery is 4800ma, or 4.8 amps. I think your battery is rated at 15C, meaning it can deliver 72 amps continuously. Which is quite a lot, it can go above that for short punches. As another example, the Orion 3600 is rated at 25C, meaning it can do a little better in terms of punch, 90 amps. But since it's a smaller capacity/runtime, it will lose voltage a little quicker than the 4800, so they are probably fairly even in typical electric heats.