It's all been well said above. Outboards are far better than not wakeboarding and my Ski Ray has been awesome for what we needed it for. It's a 1995 with a fresh 200 EFI and the "no payments" feature has been so appealing it's held me off on investing in a true wakeboard boat (which is coming on to the radar screen now).
I get to ride behind some sweet wakeboard boats and for my level the bigger, more crafted wake is very nice but I have plenty to learn that my boat is fine for. The HUGE thing I wish I had was that big platform on the back for strapping in and getting into the water. Not a huge problem, but it sure is nice.
If your just getting started then go ride behind your outboard. Until your landing backrolls, or feel the boat is the reason you can, then you have what you need to love wakeboarding.
They do perform much better than the inboard and v-drives for all out exhilaration, top speed, wake jumping, adrenaline fixes :-)