Unexpected bike temptation- opinions welcome

[azfiddle]

We went to the spring bike swap meet here in Tucson and did not plan to buy anything besides accessories.

I was getting ready to leave when I spotted a 46cm blue Surly Long Haul Trucker. I have casually looked for a touring bike - "just in case", and the only one I found before was a Trek 420 that was about that size and still too long a reach for me (although i didn't really look at adjusting the saddle position at the time).

The dealer is asking $800- he purchased it from the original owner who did not use it much. Looks like it's in excellent condition.
I only have $600 in my discretionary spending account. He is willing to negotiate tossing in my mixte bike as part of the deal to reduce the price.

I'm not sure if I will use it enough to justify it... any thoughts???