Len,
I have a very similar experience with a GT LTS that I rode many years ago. It was one of the first FS bikes on the market. Other than bombing downhills (which I never enjoyed anyway) the FS diminished the ride on flats and uphills. I sold that bike on Craigs list 2 years ago. In shopping for a replacement I was determined to get a HT for simplicity with good components and frame. I ended up buying a Giant from Performance Cycle on sale with Deore LX components, disk brakes f/r, decent front fork, and quality light weight frame for $600 with lifetime free service/adjustments. In my cycling days of past I never would have shopped at Performance (bicycling equal to Sears) but have to admit the bike has been great so far (14 months). The <$1K mtb market to be pretty lean. Most of the good bikes (quality components, frame, light weight) started in the $2K and up range. I think going for a HT over a FS in the same price braket will buy you better components and frame.
If I start to up my riding time first up on the upgrade block will be wheels, hubs, and crank set. Quality wheelsets are key when your legs are the motor.
Edit - page 6 on
this thread has a post from me with a picture of the then new Giant.