I think the reason for me to get the GGTS would be the stainless steel construction. I had two of the first generation of the (aluminum) GGTS, and while great versatile units, the aluminum oxidizing drove me nuts. It wasn't that the shine would quickly dull unless it was polished regularly (I quickly got over that.), but that oxidation on the internal threads would slowly diminish the amount of current that reached the atty to the point of shutting the unit down.
At first, the solution was to coat the threaded internals with noalox. This worked for about a month per application, but the noalox would harden and be relatively difficult to clean out before applying a new coat. Vaseline was then recommended; it was easy to remove and apply, but an application would only last for a week or week and a half before it started to lose voltage from oxidation. And they tended to oxidize shut and become difficult to disassemble if I left one unattended for too long, which diminished its utility as a backup/use-in-case-of-emergency vape.
The (imho excessive) maintenance diminished the usefulness of what otherwise was a brilliant design, and I'm concerned that the Galileo will also have the same weakness in the long run also being made out of aluminum. (Though I realize that different alloys of it have different oxidizing characteristics.)
I'm thinking (hoping, praying) that the stainless steel won't tend to oxidize as easily or quickly. Though I think others may NOT like it due to its increased weight over aluminum. I don't think I'll care if its heavier, I just want it to vape when I pick it up in the early morning.