I am of the opinion that you should go with whichever suits your eyes.
Learning, reading and spending a long time with a deck that you don't like the look of defeats the object, so it doesn't really matter whether it is a RWS, recommended or not.
Which one do you get a shiver from.
The Gilded is not a personal favourite of mine, but I am well aware that it has been extremely popular with new readers. In that, I wouldn't say it was a bad catch.
And the Fantastic Menagerie gives the whole experience a different twist. Personally, out of the two, I think that one might stretch your mind a little further. From my memory, there is an acompanying book, which was written by a complete and utter nutcase, LOL
Ain't that right, Helvetica?
Just joking.
Pick one. Stick with it a bit, exclusively. Live with it. Then intergrate the other one. Note their simularities and differences. You will get to a point where you can read them both and the beauty will be that they both read differently.
You have two good decks under your belt. Squeeze as much out of them as you can. Don't fall into the trap of casting them aside and buying one after another, after another. That never aids learning to begin with, in my opinion.
Best of luck to you, LB