I've got intimate experience with both boats. My GF had a Wake Challenger that I learned to surf on. It was actually a really nice boat -- super ahead of its time.
The Saltare will surf better, though. If you can stand to give up fuel injection and heat and the reliability of a "newer" boat.
The Wake Challenger does not put out the same wake as an Enzo. No way, no how, I call 100% BS or you are smoking rocks. It's a 22' boat but that figure is misleading because it has the swim platform integrated. It feels like a 20-21ft boat. It's not super wide, and it doesn't have a great hull for surfing. It's an "ok" surf boat but not a "great" surf boat. The saltare is a "good" surf boat but not a great surf boat. You'll get a longer, fatter wave with a lot more push. It's just science -- the more water you can displace, the better the surfing is going to be.
Here's your problem, though -- My GF bought her 1997 Wake Challenger with under 50 hours on it in 2001 for $12k. Yes, she stole it from the bank. Yes, it was worth more. But it's probably not worth a LOT more than the Saltare is at this point. That Saltare is going to need new stringers in the next couple of years and once you get all of that squared away and the new upholstery and the engine sorted and the ballast and some stereo, you're going to be in the $8k-10k range on your investment. Plus it will feel like decades in the garage.
So -- if this is your idea of saving some money, forget it! If, however, you just want a project..... I think you found one!
Former owner of a 1987 Supra Saltare. Current owner of a Malibu 23LSV.