I tried CGDA earlier this year on a whim when my interest in fivers did not survive actually owning and playing one for a couple of months. At the time I had no "gig", I was just sitting in at worship band rehearsals at church, hoping to come up to speed enough again to get a position on one of the teams which play in a rotation. So there was no risk attached to doing something goofy. Or so I thought. I went to a rehearsal ten days after switching to the new tuning and was informed that the other bass players were unavailable this week and I was on for the upcoming Sunday. Ooops! Rehearsal is on Thursday so there was no time to relearn the material in fourths; I was in for a penny, in for a pound with the CGDA tuning.
I've never looked back, I love tuning in fifths! It is not perfect for playing a lot of material written around the fourths tuning, naturally. But it is workable and in fact since virtually nothing we play is literally written out for us and we pick up most things by ear and then modify it to make it our own, the fifths tuning is as good for that as the fourths tuning at the end of the day. It gives you the single hand position range of a five string on a comfortable and familiar four string bass. If you like to dabble in playing cello music, as a surprising number here claim to do, it is perfect for that. It is uncanny how every time you are playing a phrase in a cello piece and
really wish you had
that note on an open string you magically find that you
do have that note on an open string!

Listen to violin or cello music some time. The artistic and melodic range of a fifths tuning will be quite apparent. I was reluctant to try it for a long time because it does put some notes farther apart and it demands that a single hand position cover a couple of more frets as a consequence. I thought that would be starting to get impractical on the 27 inch scale length of a cello even, not to mention a bass guitar, and obviously no double bassists would even consider going there. Except, as I eventually found out, a growing number of double bassists are tuning in fifths now! So I had to try it and it is good.
I am about to get a third Jazz bass, a fretless. That will leave me with one more bass than I have any regular use for unless I can do something with it that will make it unique. So I will probably try another fifths tuning on it. I might go with the violin tuning, GDAE, to get a "baritone" tuning. Or I might go with FCGD to get closer to the traditional bass guitar lower end. Either way, all my basses will be tuned in fifths from now on.
Ken