Making 2 assumptions:
You're used to playing parallel frets as opposed to fanned frets.
You're used to 34" scale or 35" scale. (I believe the Dingwall Combustion B-string is 37" scale)
Buying a bass (or any musical instrument) sight unseen / unplayed is a leap of faith. Sometimes your "faith" is spot on and other times…well…not so much.
Going with a Dingwall means you really want to try something a little different. Not a lot different! Just a little.
Although I have never played a Carver instrument (and I'm sure they are very good!), I took a leap of faith and bought a used Dingwall ABZ5. And I never played a fanned fret system. The "leap" has put smiles on my face.
In your case, it seems either decision would be good. Now you just have to choose the "gooder" one.
if only you had more scratch to buy both!