I think that the 700 was a fine machine when new. It is a rather old design though and even in "decent" shape, it'll probably need a good bit of TLC to get it running properly.
That's not to say that any machine isn't going to need some help (unless you're super lucky) but IMHO, it's better to spend a little more money and time and find a cheap Otari 5050.
Because of the work and expense of getting just about any used machine in the lower price range is going to be about the same, why not get one that's going to reward your efforts?
Although I haven't "shopped" Otari's in a while, it wasn't unusual to see them in the "under $400" range. I've almost bought one several times for under $250.
