IMO, I will not lend my camera to anyone, apart from family and girlfriend. Even so, there will be a lot of things to teach before the camera is handed over. For friends, it is not I don't trust them, but as what you guys had said, if something screws up, who will be answering for it.
If something major screws up, maybe can ask for compensation, but also funny. If it's a minor scratch, you also dont dare to accuse him that he did it. That is worse. I cannot imagine my camera having light scratches after lending to someone.
OT a bit which I think is far ridiculous than lending a cam... recently, my friend asked me what mod chip my PS2 was. When I told him a DM3 chip, he wanted to use his PS2 set to exchange with mine. Initially, I thought it was for a few days only. But as a matter of fact, he wanted a permanent exchange.
I rejected him, saying it makes no sense - 1) My set is only about 2 months old and 2) I paid 100 dollars more for a DM3 chip. His set was about 2 years already and having a older chip set.
I just wonder why he did not thought of such things, and actually asked if can exchange between the 2 sets or not.
Haha, its like a guy owning a D70 with its backfocus calibrated already, while mine is a older D70 with backfocus problem. And I asked that guy if I can exchange my cam with his, when I have the option of (calibrating at Nikon be it FOC or at a cost). Though both are D70, it makes no sense at all...
Just some thoughts...