Also work got me a Dell XPS which I was really liking but it has now died twice in two weeks, meaning that I've lost 4 days work over that period (due to only saving locally). Is a Macbook a poor choice for a work laptop?
Not at all. There's potential for some file incompatibilities but as long as you use the same Microsoft Word/Excel etc as everyone else you'll be fine.
Also work got me a Dell XPS which I was really liking but it has now died twice in two weeks, meaning that I've lost 4 days work over that period (due to only saving locally). Is a Macbook a poor choice for a work laptop?