As a die-hard Dragon Warrior / Quest adherent, Guadia Quest is a surprisingly excellent riff on the classic NES games. Don't know how long it'll actually last, but it's great, nonetheless.
All of it has been fun, although Haggleman 2's last challenge was a bit annoying for me, for some reason. Maybe because I was up too late playing, and all my skills and patience had gone down the drain at that point.
Rally King gets annoying. It's not bad by any stretch of the imagination, but it can be way too easy to spin out, and the boost mechanic usually gets you in more trouble. It's definitely not something that can be abused, like the boost mechanics in Mario Kart.
Anyway, I figure I'm going to buy this legit. I've enjoyed it far too much to deprive them of a sale of an excellent game, and I'm interested in seeing more of these cross the pond.