Thank you! Well I'm sure the Dvorak layout is much better than the QWERTY layout, but from what I've read, Colemak makes it easier to use default shortcuts such as Ctrl+X, Ctrl+V, Ctrl+Z...
I need to be on holiday to learn the new layout though.
If you're willing to put in the time to learn a whole new keyboard layout then you should be willing to put in the time to change any default shortcuts that you don't like!
But personally I haven't found them a problem at all, even in Emacs.
I wouldn't say hard, but it can take me a few minutes to get back to full touch typing. Before switching to Dvorak Type 2 (plus <Alt Gr> + homerow mapped to <[({})]> for programming) I did already have to switch between QWERTZ (German) and QWERTY (UK, sometimes US) on occasion, which may have prepared me for it. Though the differences between QWERTZ and QWERTY are pretty minimal compared to Dvorak.
Personally I find it damn near impossible to use QWERTY after going to DVORAK, even after several years. As for someone else using my machine, well my friends refer to my work machine as having "the klingon keyboard". Handy for keeping people the hell outta your workspace though ...