Not sure how old the Jetta is you're speaking of but I test drove a friend's 2000 Jetta 1.8T w/5-speed and thought it felt very rubbery and vague. Maybe I was spoiled by my S2000 at the time. I also test drove a 2003 Jetta GLI, before buying a 2003 Jetta GLX (short-lived, less than a year), and thought it's 6-speed was a little better but not much. Even my dad's 2001 Corvette feels a bit rubbery to me.

I really like my 6MT now. First gear is a bit notchy when the transmission is cold but overall the feel is very good. I'd put it up there with some of the best manuals on the market.