The Laguna Revo is new on the market in the last few months.........that is why there is not much info from users to be found. The customer service issues experienced by some in the past with some older models was noted on some forums. I have not personally seen the new REVO lineup, but did look at them on their website.
I would personally want to know some facts from a technical aspect and not just hear a sales pitch to make me where I wanted to go that way over the Powermatic. Be aware of this.......there are probably two maybe three actual manufacturing entities that make lathes in the PRCC or Tiawan, but the quality control in a ISO 9001 or later certified facility will make a difference.......as will the demands of the seller, like Powermatic.....they have tight QC controls and are very responsive with customer support.
I have a Grizzly 18/47 lathe.........it has served me well and been a stellar performer for 3-1/2 years........so the REVO may serve you well, as I think some Laguna and Grizzly and Busy Bee [Canada] and others [Baliegh 18/47, etc] are all made by the Burt Group from what I can determine.
All that being said.....if I had the funds and was getting ready for my "lifetime lathe" it would likely be the Robust American Beauty, but that may not be in the cards for you.
I don't think you can go wrong with the 3520b, although there are some reported problems with them from time to time......Powermatic is quick to respond when it happens...............good luck with your decision!