Going to have to go with COOL purely for the reason that lots of people I knew wanted one back then. (But hey, my maxtrax came with cheap elastomer suspension so I was sorted...)
Absolutely 100% Cool.... I'd probably still consider putting one on my Raleigh Dyna Tech. Can you imagine that... double cool... a Dyna Tech AND a flexstem!
There are a substantial amount of retro "things" that don't work particularly well in modern company but are still considered cool - and in my book this is firmly one of them.
If it hit the market today it would bomb, but as a piece of kit in the 90's it was a credible alternative to suspension forks (which lets remember, weren't exactly cutting edge compared to todays offerings...)
The one piece bar/stem combo looks fantastic even today.