I'm not sure about why I would need to worry about "do it over". If I really want it, I buy it. If I really hate it, I sell it.
.22 - Browning Buckmark Target
.380 - No real use for a .380, but my mom has a Sig P230
9mm - I am now carrying a Glock 43, but I own a "few" others
.40 - STI Edge (for target, not for carry)
.45 - Thunder Ranch Special (Still my favorite shooting gun)