I have installed dozens of cabinet decals over the years and if done right, they do require a ton of prep if you want them to look great. I usually clear the cabinet so they go over it like a sheet of glass.
I have installed 4 sets of Radcals and I still prep the cabinet the same as I do traditional decals so the work is the same.
However, many folks just slap the radcals over the cabinet without much prep. I would not take the easy way out on this since you can see through the radcals of what is actually underneath.
Purists will always lean towards traditional decals, however, IF you want a thicker super glossy look, then Radcals are the way to go.
Applying Radcals aren't as simple as many folks think. You have to route out the holes for the buttons, hinge mounts, etc. and sometimes they are to long and you have to trim or edge to the wood and this can be very tedious and time consuming. With traditional decals, it is much easier to trim these areas out.
I am glad there are dual options out there for both types of consumers and I found that most of my new clients do like the super glossy thicker Radcals. I do still have a few that prefer the traditional look and want it to look as original as possible too.