I'm actually surprised most people think friesians cross well and pass on their look. I think its more that people are finding these lovely stallions that crossed well but if you search for friesian crosses on dreamhorse.com etc... they just don't look very friesian-y to me.
I think it depends on the individuals being bred. Our stud passes on a distinct look but many others do not... that's why I've never cared much for cross breeding them. You have to really know what you're doing.
When I was younger we had two friesian/paint crosses and they were lovely but you wouldn't know they were from friesians.
Im really not sure where people keep getting this Appy mane thing - I know more QHs with cruddy sparse thin manes than I've ever seen Appy's with similar. Most of the Appys I've known have thick manes and tails.
But this guy is a gorgeous example of a Friesian-App cross... maybe a tad butt high, but he's gorgeous and a great mover. With a full mane and tail :p
Tried to add this link of searches to my previous post but I waited too long. They just don't represent the friesian enough for me to desire that cross if you're looking for a horse that "looks" friesian-y. And there isn't a consistent "look" they all share... some just look like thoroughbreds, some look like mustangs, some looks like warmbloods and others look like percheron crosses!