The MG is a more comfortable car to drive and easier ingress/egress. No, I <span style="font-style: italic">didn't</span> say it was a more "girly" car (but some folks may). :lol:
And as usual, the Triumph is more of a driver's car. However, both unique and beautiful automobiles and literally guaranteed to turn heads wherever you go. You really can't go wrong either way.
I'll take a Triumph over an MG any day, simply because I've owned more Triumphs over the years. Having said that, I think the MGA is more attractive from a styling point of view.
But if you want what is possibly one of the planet's purest driving experiences, get the TR-3, I'd say.