I don't believe WGT can just put any name they want to their virtual balls, there has to be a contract between them and the manufacturer. We have to wait and see what will replace the current, very extensive, range of Nike balls but you can bet your own balls it won't be any cheaper than the ball being replaced.
I believe Callaway has suffered a big loss recently. I have switched from my long loved and trusted L33 ball to the L51 Volvik and have to say it's a big improvement. I found the Callaway just wasn't playing the same as it used to, or how I always remembered it playing anyway.
The Volvic is obviously a bit of a price hike but within my budget and the results are promising so far.