I don't personally but a good friend of mine has just purchased a GP/Jjump and a dressage one.
They are attractive looking, appear well made, nice leather and according to friend very nice to ride in. All in all a good saddle for a very fair price.
I have a K&M Cob GP and i love it! Its so comfy and can be altered to fit my cob so well its almost made to measure!! Its lovely leather and very well made ive had mine nearly a year as I saw them as soon as they came out and managed to borrow one to try then got on the waiting list to buy one. I rank it well above my Ideal H&C which is the one i had before.
I too have a Kent and Masters and I absolutely love it. I have a GP one and love it. Really happy with it thus far and have no complaints whatsoever. Saddler recommended it to me, and this is what i hear alot when these are mentioned, so they must be doing something right (either that or the saddlers I know are heavily commissioned.. lol)