I have a fair few crashed on my 'mac' but I assumed they were due to the way it was being run. My friends mac has fewer but he still has them and his has a proper one and only a couple of months old.
Personally I think that getting a mac can work out cheaper if you have a visual impairment as you don't need to buy the specialist software you do for windows. (Well, unless you have windows 7
but that's a whole other story).