The 2027 neck is NOT thicker than the new UV necks. I have them both, or used to, they were backups to each other when I couldn't decide which one I liked more.
THe neck profiles are different. The UV neck has steeper sides and a flatter back giving it more of a beefy feel, more D shaped if you will. The RG neck is more wizard like, it has a softer shallower feel. The actual thicknes from fretboard to back of neck may be the same as the UV for all I know, but the profile is such that it feels much thinner.
In my book, they both are fabulous, but I prefer a little more meat so I loved the UV neck.