These things can be good if you feel you need them. There is also a service in Seattle that will make you over and take you shopping en femme. And there's another (at least one) in NYC plus probably other places. (I've heard of one in London.) Many of these are aimed at cross-dressesrs but will gladly accommodate early-stage TS's too.
For me, I sought out advice aimed at GG women and applied it to my specific body type, facial structure, coloring, etc. I didn't feel the need to go to trans-specific services, but I won't fault those who do. To each her own. Whatever works for you, but I am wary of these kinds of things in general because sometimes they are just looking to make some easy money and take advantage of the vulnerable. (DISCLAIMER: I don't know anything about this particular service and it could well be legit.)
Just my 2ยข.

- Kate