If you don’t need to sell the 4’s I’d keep them, or one at least. I’ve been playing a 5 for a long time. It’s home for me. I have a cheap 4 string jazz. Never play it. I do find myself making my 5 sound like a P a lot lately. 95% of what I play could be played on a 4. I keep playing a 5 because of a couple tunes we do and for church, where key changes are as frequent as my heart beating. Just makes it easier.
