[brijar]

Like jhautz said, the BK Warrior 9918 ESC has been replaced with the BK Warrior 9920. I had a 9920 in my E-Maxx. The ESC is what made me have to sell the Maxx because it fried twice on me and the repair bill is just too much the second time. I would highly suggest the Mamba Max speed controller, as it only costs $112, can do just as many amps, is more programable, and is probably smoother, not to mention the flat repair rate of $50 for it, rather than $100 to fix a 9920. The Mamba ESC is also a lot more durable. 9920's only have heat shrink around them to protect them, but the MM ESC has its own hard case to protect it. The Mamba ESC also has its own soldering tabs so you can use your own wire, but with the 9920, you'd have to remove some heatshrink to get to the soldering tabs, if there are any at all. You won't have to mess with little red and black jumpers for programming the Mamba ESC like you would to program and setup the 9920. The Mamba ESC is a lot easier to mount, IMO, having a hard case that you can use screws with or velcro, rather than having to zip tie the 9920 down. The Mamba has a programmable low voltage cutoff, so you won't have to get an external one like you would with the 9920. It also has a colorful green heatsink:). I think the only advantage I can see in the 9920 is that it can do up to 20 cells or 6s, but the MM can only do about 5s. Don't quote me on that, as I'm not sure.
This is just how I view the two ESC's. I could be wrong in some of my views, but the clear winner to me is the Mamba Max ESC.

Good luck,
Brijar!!!