I have ridden both Mr. Freeze rides, and I find them to be extremely temperamental. Sometimes the ride won't bang my head to much, and other times it seems like it's a boxing match. However, I've never ridden a Mad Cobra model, so I cannot compare.
Every time I ride Mr. Freeze, I think, "Incredible launch, but what the hell happened with the rest of the ride?" I find the top hat fun, but nothing to ride home about. The overbanked turn is cool, but the spike does nothing for me--I never feel any big sensation coming back down (and I didn't on S:TE either). I always get off feeling like the ride should have done some other things. But I am not a fan of shuttles, so perhaps I'm biased against it.
Maybe with the lapbars the Mr. Freeze rides would be a completely different story for me. But until then, I find them to be a decent ride at best, and certainly nothing to write home about. It would not be a bad addition to a park, but with all of its maintenance problems, I think there are other coasters that would be a better investment.
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According to the "official" count, next year's new coaster lineup will feature 17 Arrow 4-Ds, 21 TA2Ks, 34 B&M floorless's, 17 Intamin Gigas, 12 beemer flyers, and 247 CCIs. And oh yeah, CP will receive one of all of these.