Larry..I think it depends on how you intend to use it. IF pulling a trailer is going to be done a lot and IF your in hilly country them go for the 292. But if all you intend to do is use it as a driver for weekends, etc. then there is certainly nothing wrong with a 250. Most of us really don't want to drive these trucks like they are brand new so we slow down and enjoy the ride.
Pick up a copy of the Chevrolet Inline Six Cylinder Power Manual by Leo Santucci (2001 CA Bill's Automotive Books) online probably from Amazon. It has a LOT of info on the last generation of Chevy inline engines. (194,215,230,250,292)
Just be aware that all of these are more expensive to rebuild/upgrade than those bent (V8) motors as this always surprises all first time guys.
Also you'll wan to check out Inliners.org for even more info and tech advice.
