i think you need to realise some people arent born thinking they own the skinning world.
enix, your skins get much better each time, and as for the arm muscles, if your talking about the model, ill wait untill your on msn, so i can actually look at the model. although for now id just say it looks like his arm is scaled up where his bicep is, it isnt actually formed like a bicep.
look how the pectoral muscle flows onto his shoulders and then look how the bicep actually starts up near the "armpit". hope this helps a little. like i said, catch me on msn