I prefer fillet-brazing over lugs. I like the smooth look. But, a good frame builder should be able to build you a strong frame using either technique.

And as Judah pointed out, with fillet-brazing you can choose any geometry since you are not limited by stock lugs. But, for me this is a moot point since few of us will be ordering any frame geometry out of the ordinary (77 S/T angle, 76 H/T angle). Most of us are sticking to 74/75 S/T and H/T traditional angles.

I would not bother with tig-welded custom frames. What's the point?

So yes, how a frame is joined together is an aesthetic choice. More important is choice of tubing. For the street, cheap and strong, for the track, light and strong.

Everything is a compromise, and for me Columbus Zona is a good choice.