I tried a guitar today, was a 2nd hand Washburn Jumbo acoustic, with a sunburst finish and tortoiseshell pickguard. Was a bloody brilliant guitar, I'm hoping to buy it. Only problem is, I don't have a clue what it is - it's not on the washburn site and google image search yields no results. Just wondering if anyone knows what this guitar is, and if so, how reliable/durable it is.

It's almost impossible to identify with that description. We need more info, or better yet, go back, try it again but this time look in the sound hole. There should be a label with the model number and serial number.