I used Match twice, successfully. As far as their suggestions go, I'd guess they're mostly just keyword matches and guys that secretly viewed you but not confident enough to say hi. I never took that aspect seriously.
I'd recommend it if you want to go on some dates; get some face time, instead of waiting patiently for Mr Perfect to just happen to cross your path at work or the gym. I thought the cost was insignificant, yet just enough to weed out guys that weren't relationship oriented. Not that unexpected hookups didn't happen, but isn't that part of the dating process?...the qualification process?
I'd also recommend managing your expectations. Some of the dates I was least interested in, turned out the best; same for looks in person. Others, that seemed like they were going to be the one, after endless intimate emails...sure...why not commit to dinner for a first meet, turned out the absolute worst.
If you are actively interacting, the site will be actively promoting you. If you drop off, so does your profile from the front page.