I have both...
I much prefer the Creative Grids ruler to the June Taylor strip ruler. the JT one was a thinner acrylic, I think. This make it too easy or me to make crooked cuts with it.
Martelli mats are hands down my favorite, the rotating mat included. Unless you are in a hurry to get it, go to their website and register for newletters/specials. They offer a discount several times a year; I bought mine at 50% off. Have had it for years with no problems.