I have a mini horizon. It's not a bad press, it has some nice features. You lose appx 3" in the front and 6" in the back. I use Newman's in mine. Even though they list the max screen width as 20", the 21" fits without any issues. I use 21x26 frames for bigger designs. The screens are pretty tight though, but you get used to it. I am liking the idea of cutting my squeegees to 14" as well.
All in all, if I were to do it again I would get a full size. But if you don't print anything too crazy in size (which I don't) and you are limited on space, it's a nice press. It will just limit you a little with bigger prints and it's a little tighter with the squeegee floodbar set up than a normal press.