I got one of the early 453's that came out as CZ first moved the set trigger feature down into their rimfire line. Normal mode I'm probably at 3.5-4lbs (still breaks nice), but when set, the trigger on this one trips at a consistent 5oz! Great for off-hand shots, the occasional long distance snipe, or work at the range.
I would go for the SST. I know some folks don't like 'em, but I think they are neat.