The only negative thing I've heard about the smartshock was that the theory was sound, but it didn't actually... you know; work.
Have you got the full kit then? Fork an' all? I'd be interested to know how it rides in reality; the reviews in the 90s were always fairly good, but with most bias on how cool they looked rather than actual race-winning performance / weight.
If you're interested in price; some non-smartshock carbon girvins went for £155 (bit expensive) a few days ago, some standard alu ones (also linked above) went for £56 (bit cheap) last week. The upcoming smartshock ones look in good nick so they'll probably go for around £150, unless some crazy 90's zeitgeist collectors get all excited and kill each other over them and spend £1,500...