Unfortunately, about 2-3 years ago one of their reps talked me into subscribing. They gave me a break and only charged $2000 because the rates were going up the next week to its current cost and I have my own website, so I didn't need their subdomain.
My experience with MFQuote is:
Very little work was posted around my neck of the woods (Southern California). Most of the work posted was in the mid west. Great if you are in the area.
Lots of tire kickers posting work, their only intention to get prices, not award work. One of these companies turned out to be located 2 miles from my shop. My wife called the engineer who posted on MFQ and asked if they were outsourcing any work. His reply? "We already have shops we deal with". That job they posted? they cancelled it. Another clue about tire kickers - they never award the jobs they post.
Many of the companies posting work are price sensitive.
Most of the machining work is widget/production oriented, not the type of work I do. When I signed up the rep told me there are lots of jobs posted that are exactly what I'm looking for (3-4 axis prototype, molds, models). That turned out not to be the case. I was mislead about the type of work that gets posted.
With 2 months to go before my subscription expired I did finally win one job. I only made $900 so I lost $1100 to MFQ. Anyone paying $4200 better be able to absorb the possiblity of not getting any or very little work.
To be fair there are some shops that claim to have won quite a bit of work through MFQ, but I have some serious doubts about most of those claims. There have been many postings about MFQ on other websites and the majority of those posts are not favorable. I have talked to other shops who tried MFQ and not one of them got any work.
If you do decide to try this or any other similar online quoting service, do your homework and spend some research time talking to as many shops as you can who have used the service.