I have an HQ16 and adore it. Can't imagine ever switching. I choose it because it had more options for the money and I didn't like the way the TL sewed at all (plus you were required to purchase a Grace frame with the TL, and I wouldn't own another Grace frame - only a 4 pole system, which is what the HQ has). I also wouldn't have a stretched machine - I wanted something more industrial so it would hold up. I love the ergonomics of HQ's, no maintenance like most others (one drop of oil per bobbin change and that's it - it's one of the few non-stretched machines that is self-contained). I adore that I can use different top and bobbin threads, which most machines can't do. I can use any thread don the market, again that's rare. And I love the user help desk at HQ. They are really awesome.
And right now, because there are so many new models out, you can get a used HQ16 for so much less than I paid (join the Yahoo HQ16 group and check out the for sale database). There's nothing wrong with the machines, as they're pretty hard to mess up, but people are upgrading to longer arms. I love the 16" reach as it's just right for me, and so far, there's nothing I've found that it can't do. And I will never own another frame system except a 4 pole. I don't want to have to deal with the take-up pole riding on the machine bed and constantly having to readjust it as the completed quilt grows larger on the take-up pole. It's one more adjustment per turn that isn't necessary, in my opinion. (Some folks don't mind, but I've been there and done that!)
This is just my 2 cents :) If I ever do decide to upgrade, I will stay with the HQ brand. Many professionals have switched from Millenniums, A1's, etc. over to the HQ brand now (Kimmy, Jamie Wallen, etc.) because they're so great.
Debbie in Austin
PS If you decide to purchase a HQ, I do know a great online dealer who has a huge following for his customer support. Send me a message and I'll hunt up his info, when you're ready to buy.