Topband: Quarter wave vs eighth wave radials?

[Glenn and Barbara Kurzenknabe]

Hello Top Banders!
I am sure this has been kicked around before, but here goes anyway.
I am presently using an Inverted L, with 4 quarter wave, elevated radials on 160.   Results have been "acceptable". I am planning to take the elevated radials down and go to on the ground radials.  The question is, what is the thinking on "quarter wave" vs "eighth wave" on the ground radials?   I realize that "more is better" but how does that equate to dB's, in the real world?   I suspect I'll end up with about 20 or so radials for starters. Please respond directly and I'll try to post a summary of the various thoughts.
Thanks guys!
73
de Glenn, K3SWZ