Yes, I do regret my first 5er. It was an Ibanez SR505 and it was a great bass. And I did a LOT of testing in stores to be CERTAIN that I preferred its neck and string spacing. Brought it home and started playing it exclusively. I had a little trouble at first but basically it played as well at home as in stores. But it never got any better, in fact it got worse. I persisted for a while but no joy. So instead I tried tuning my four string in fifths and that was instant love and the affection has only grown deeper with time. For grins I tuned the Ibby in fifths briefly and that was interesting but I still did not like it. Eventually I sold it and got another four string instead.
I liked having a main bass and a backup even though bass playing is only a hobby for me. I have a "gig", the praise band at church, so it was nice to know that I could cover my commitment even if my bass failed. But it was also kind of boring having two basses that basically did the same thing, I wanted to try chording more and the upper three strings on my bass were best for that due to their higher pitch, and I had a set of GDAE strings laying around from the old Ibby. So I tried that on my backup four and I liked that too. It goes nearly as low as a traditional EADG four and it is nice for chording.
But I lost the low C and that is somewhat important to have in church music. How could I have both at once? The obvious answer was to try another five tuned CGDAE but this time with a wider spacing. The one I got was a used Fender Standard Jazz V from here on TB. It's string spacing is a scant half a millimeter wider than the Ibby's was, 17 versus 16.5, but so help me that actually makes a big difference to me. With some work (a new bridge) that could be pushed up to 18mm but 17mm is working out for me. I am still more comfortable on the fours but I feel like I am over the hump now and that a wider spaced five will work for me.
If you want to try a five be prepared to take more time getting used to it than many here report. It is one case where I recommend buying used since you may have to try several configurations for more extensive times than store trials permit to find the one that works for you. If you buy used you can buy/sell/buy... at little to no loss. And be prepared for the fact that you ultimately may not like it. I am still not sure the fiver is going to stay with me. It does work for me on the second attempt and it does give me some capability that I don't have on the fours: better range for chording and the possibility of retuning that highest string as needed to make playing a few parts easier while retaining plenty of range on the lower four strings. Those are things that may come in handy occasionally when the guitarist can't make a given Sunday. Most of the time my fours are all I need though.
Ken