about buying a used flash

ive been thinking about getting the metz 48 for a while now and i was pretty well set on that, as the price is right at $250. i found a local shop though that has a used fl50 on consignment for $250.
the only problem im having is that i dont know if i should worry that i am going to get a flash that might only last me a couple of months before it burns out or something. is there a problem with buying used flashes, or is it something that is usually a pretty safe purchase?

if it makes you feel better about it, i got my metz 48 used

actually if it was a metz 48 or an fl 50r, i wouldnt really be worried about it. atleast those two havent been out for a very long time. a used fl-50 could be 5+ years old.