Having had both I would say T/C hands down. As far as the obvious quality of the two there is no comparison in my opinion, with that going to the T/C. Even if you are not contemplating adding additional barrels at this point in time, that will pass once you get to shooting a T/C and you find how easily it is to swap back and forth to add more calibers / cartridges to you battery.
Larry
Hrm...let's see...
TC: Spend almost $300 for a new barrel, add base, rings and scope, use a flat blade screwdriver to remove forearm and hangar bar (if you have a hangar bar on your barrel), drive out the hinge pin, put new barrel on, install hinge pin, put on hangar bar, put on forearm, have a new caliber.
Handi: Spend almost $300 for a new gun, add base, rings and scope. Have a new caliber.
I think the Handi is probably the easier caliber switch. The T/C gives more options and is easier to find in exotic chamberings without necessarily having to contact a gunsmith.