My razr has a replaceable battery, but I'll tell you what, whenever I open up the battery cover to get the memory card out, the whole compartment is full of dust and dirt. I would honestly have a sealed battery that requires some disassembly or service to repair than have to worry about all this crap getting into my phone and ruining it.
Also, whenever I see a razr, or any other phone for that matter, hit the ground, it always breaks into no less than 4 pieces. I've seen this happen dozens of times on campus.
If I had the $$$, I'd prefer an iPhone, but for now, I have to be careful not to drop my phone, and I'll clean it out every two weeks or so.