As long as they can make the striding, I don't see there being a problem. My horse is just over 15 hands and I have to really get her to lengthen in order to make a 12 foot stride (she's more comfortable at an 10-11 foot stride).
Seller was very honest, dont blame him one bit. It is too bad, but I am also very lucky to have two incredible beasts. I was never looking for another one, just had the opportunity to try her out and just so happened to fall in love with the way she went. From what I hear, she will have a wonderful home with a FAR better rider than I, and Im sure will be a top hunter in a few years time. Thanks for all the quick replies though, the more I ride the smaller ones the more I start to prefer that to my 16 and 17hh ones!