(Warning, thread hi-jack in progress...

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Yes, I am quite happy with the Forzas. Bang for the buck, they're hard to beat. The list price you'll see everywhere for them is $220 per seat. Steve Pierce undercut that price by a healthy margin.
They do fit in the Miata, but not without some effort. Usually, the seat bottom is the problem area with race seats in a Miata, and the Forza fits with room to spare. The problem area is actually higher. The Forza has a wide section at the sholders, so when you close the doors, the seat actually makes contact with the top of the door panel. After a month or so, I actually have a small indentation in the padding on my panel. You have to make a concerted effort when closing the door, or it won't shut completely. It's annoying for a day or two, but you get used to it.
Chris Schimmell installed my bar, seats, and harnesses. He actually had some trouble with the sliders Corbeau sent. He modified them to work, but we later found out from Corbeau that they manufactured them incorrectly. The Driver's side slider was drilled for the passenger side, and the same for the passenger side. This offset the seats out so far that the doors would barely close at all. Chris modified the brackets, and it works pretty well now. I could have sent the brackets back to Corbeau for correctly drilled ones - they offered.
For spirited driving, they are great - the effort you're used to exerting to hold yourself in the seat is subtantially reduced - I'm sure the 5-pt's have something to do with it also, but I'm much less tired at the end of a 30 min session now.
The main reason I got fixed back FIA-approved seats is because of what happened to Rob Plank a few years ago when he wrecked his Miata at VIR. He was using stock seats, and the impact of the crash actually broke the seatback mechanism. Rob's head smacked his roll bar pretty hard. Obviously he's fine now, but I don't want to take that chance.