A Malibu is a big step up in every way from a Moomba, including a big step in price.
Depends on what you can afford, and if you value the things the Malibu offers over the Mobius.
It's rare to even see these two compared, since the Mobius is a price-point boat, but most Malibu's, except their Ride line, are a premium-level boat.
I could list the differences, but all you need to do is look at both, and drive. You'll see. Then you decide if the Malibu warrants the price premium. Both will pull you on a wakeboard, in the same way a Chevy and Cadillac will both get you to the grocery store.
The Mobius is a very well built boat, but built to be less expensive, with less creature comforts, features, etc. A Malibu is well built, and does offer more comfort, higher-end components, more features, etc.
The same company that makes Mobius boats, makes Supra, which is a higher-end boat as well. I had an '04 Supra and it was a very nice boat.
Anyway, different people value different things, so you just need to check out both and decide.
By the way, there is no such thing as Malibu xlv. That's a Mobius model as well.