Ok, so I have only been in the sport for a short while. I have been using a 98C until I stumbled upon a Matrix at a garage sale. I bought it for $75. The person selling it was just the Dad of the kid selling it. He really didn't know what he was doing. But anyway, I was wondering if I should know anything about it such as upgrades, warnings, etc. Also I was wondering where the battery compartment was. I took the grip off to get a better look but I couldn't tell where it would be. Also could you post some pictures of your Matrix to see where I'll go with it?