I’m a 16 gauge fan myself, I grew up toting one in the field quail & squirrel hunting .
Although it was a modern gun, it influenced my choice later in a smooth bore gun.
My choice was an easy one, thirst I called Tip Curtis asking about a barrel .
While at his shop he showed me a 44” Colerain barrel in the white smoothbore with an L & R lock, which I’ve had zero issues out of... other than getting the correct ball size.
Target was shot without a patch , benched at 25 yards..
This was after numerous attempts at shooting patched round balls of .620 & .626 size from various Vendors.
Finally getting some .648 round balls that the above target was shot with using 70 grns of ffg .
Since then I have found that a .642 hand cast ball shoots well with out a patch also using the same load.
Good Luck in your choice, the only advantage I see in a .62 would be the availability of store bought round ball choices... over what’s available for a 16.
FYI my bore mics at .653...so shooting ffg or fg every 4 or 5 shots I run a damp cleaning patch followed by an alcohol patch prior too reloading.