Both mine have it. I think it's a love or hate thing; if it fits it's great if it doesn't it's like any other badly fitting saddle. I am lucky my gelding is a 'Mr Average' kinda guy so a MW 17.5" Wintec 2000 fits him very well. I can't use it on my friend's mare because she is a totally different shape.
I have a cair wintec 2000 saddle that I have used on my mare ever since I have had her. It does fit her - and is regularly checked for fit. She always went ok in it.
A couple of months ago I brought a wintec isabell - but the flock one. I was partially swayed by the price / comments on here, and after speaking to my saddler.
My girl goes soooooo much better in the flock saddle - comparatively the cair panels are so hard and unforgiving, where as the flock panels seem much nicer.
I guess it depends on your horse ulitmately - but I definitely would get flock if I needed to in the future.
I my experience I'd say the flair is better, only my opinion though!
The cair panels are a lot firmer and although mine is great on the horse I don't think it's as good as the flair system. The flair system I've had for about 10years, and with minimal adjustment, has been great. The panels are softer and it moulds better to the shape of the horse.
You can tell how old mine is hough, as I think they're now called WOW saddles!!!