On hand finished violins the antiquing is usually done with very thin coats of artist oil colors.  With the more mass produced instruments it is more often done by using tinted varnish/finish.

In either case, the difference between thickness and etc between antiqued and non-antiqued will be so slight that it shouldn't affect sound to any appreciable degree.

So it all comes down to what look you like best.  You are the one spending money and who will end up looking at the instrument the most.