A mentioned prior, there is no "best". I can say that a good UQ is much more comfortable to me than a pad.
It is really hard to describe the difference. A pad (if thick enough) will keep you from getting cold. On the other hand, a nice down UQ will actually warm you up.
A CCF pad is pretty much indestructible, and impervious to failure from getting wet. That same ability to resist absorbing moisture will also often leave you with a wet back from perspiration.
I use both. When I'm in an environment that is likely to be extremely wet, I'll go with a pad set up. If I'm likely to have to set up on the ground a time or two for whatever reason, I'll go with a pad. However, I prefer the comfort of a nice down UQ.
As far as the 1/4" GG pad goes, I don't find it all that thick. I believe it is rated at an R1 or thereabouts. That will take an average person down to 57 F. Most places I hand get at least that cool even in the Summer.