There's a pretty big breed split with appaloosas. ApHC is the main appaloosa registry. Unfortunately a lot of "appaloosa" horses being bred now are glorified spotted quarter horses, usually bred for halter. Their conformation is typically less than ideal for what I like to do so I avoid them entirely.

With appaloosas, there are a large number of horses marked "F-[registration number]". This represents horses which were "foundations" of the breed (along with horses under registration #69999 for FAHR). Foundation-bred these days means the horse came from those lines and their "foundation" percentage is at least 75% by blood. These are horses that were not outcrossed to QHs, TBs, etc. recently, as ApHC allows.

This baby represents a lot to me, having just put down my foundation mare earlier this month (it was a long time coming). He will hopefully be my low level dressage, jumping, and trail partner but I like to float around the disciplines and am always trying something new so if we find he likes something else more, I'm not opposed to trying it. He'll be with me for life. There's a lot more being taken into consideration here than just what he can do for me!

SO HARD!! I haven't even met him yet. I'm so nervous for the importing process, I've never imported a horse before but thankfully his breeder says it's easy.

I’ve only ever known the QH-with spots looking Appys

I had a couple of people at my barn ask me why the hell I got another appaloosa considering the disciplines I ride right now, so you're not alone! Conformationally he should be capable once he matures, his sisters are pretty uphill.

You absolutely can get them around 15hh. This guy should end up around 16hh but my last mare was 15hh. I mentioned in another comment but a lot of appaloosas are QH crosses (it's allowed by ApHC) so you'll find most of them have downhill builds, post legs, and straight shoulders. You CAN find appaloosas with better conformation for English disciplines but being FAHR registered is not a guarantee with that either so you'll have to find a breeder producing the type you want which is hard. If you let me know what area you're in I could possibly point you toward someone.

Temperament-wise I maintain that these are the sweetest horses you could possibly get your hands on if you respect them and keep their emotional well-being in mind. They are tolerant horses and they put effort into their work.

Oh I absolutely love those lines. My old mare was by Chocklate Confetti and those lines are still floating around today too, another popular big name. I'm not comfortable posting my boy's lines because they are linked to irl me but feel free to message me!