Well, I have a Mutoh VJ and I apsolutely LOVE IT!!! It prints much better than the Roland Soljet I used to print with. The banding, or lack there of, is true. They aren't BS'n you at all. So, my advice would be to get the Mutoh.
I went with the XC-540 and absolutely love it. I to have not experienced any banding. If you use the correct profiles then you shouldn't have any banding with any printer.
Visit the the dealer and see both machines in person. Bring your own test file and print that on each machine and compare.
I personally went with the Roland because I could get better support locally and because it comes with a 2 year warranty. If you buy one before the end of the year I think they are offering a 3 year warranty. Also the Roland seemed a little more solid when compared to the Mutoh. The XC is built like a tank. I've had it for about 6 months and have had ZERO issues.
If you need less maintenance and a the best warrantee in the industry you choose Roland.
If speed is the game choose a VJ as i believe they are a bit faster, not much but faster.
As for banding its a myth. All machines print in bands. The difference is Mutoh prints in wave patterns so the long band that everyone is accustom to seeing isn't as visual.
Also if you print in 720x720 on a roland you won't see banding either as I believe most VJ guys do. Demo both but I will say this. There is no better convenience or satisfaction than having a print & cut in one machine and a minimum 2year warrantee which nobody offers. I believe you can get 3 year warrattee now as well att no charge WOW.
We own 3 generations of Rolands and consider Mutoh a serious Roland competitor.