I actually have both tanks, an Elos 160xl at the store and a 100g ReefSavvy tank at home. I'm local to miami, so I know Felix fairly well. In my opinion each tank has its pro's and con's...
ReefSavvy
Pro's: The main thing that I like about a ReefSavvy tank is the hybrid overflow or the Ghost overflow if you choose to go that route. The main focus being surface skimming. The larger Elos aquariums (120, 120xl, 160, 160xl) have a much smaller overflow in comparison to the size of the tank with very little surface skimming. Felix tends to apply more focus on this issue.
Another pro would be Felix's customer service. Anyone who's dealt with him knowns exactly what I'm talking about, top notch.
Con's: 6-7 months lead time.
Elos
Pro's: Elos tanks are all floating bottom in design. Although ReefSavvy tanks come with what is called a phantom bottom, there's still a piece of acrylic sheet glued to the bottom of the tank, which in my opinion kinda defeats the purpose. However, Felix is now using red acrylic as the base sheet and I must admit that it looks pretty sexy! Next, Elos only uses one bead of silicone between the actual panes of glass. They don't do the seconded layer which is called a "wet seal." Although ReefSavvy does precise and extremely clean silicone work, it has a much wider spread of silicone around the boarders of the aquarium giving it that picture frame look.
Cons: I was expecting more from the stand. Although it looks very nice visually and I'm sure its quite durable and will stand the test of time, it kinda has that Ikea feel to it. Even more so when you have to build it yourself. Secondly, Elos equipment (skimmers, lights, controllers, etc.) are overly priced and usually fall short in comparison to their fantastic and well exectuted glass aquariums. lastly, you'll definitely won't get the same customer service from an Italian base company vs dealing with Felix one-on-one.
If it was me, I would first try to bribe Felix with a four month proposal. If that's a no go, I would simply order an Elos tank, have it delivered the following week and call it a day