I love my HQ. I haven't read all the suggestions, so hope I'm not repeating. I do consider these items to be important. Having said that, here are my suggestions:
1. Look for a frame with 4 poles. This way, you're not constantly having to raise the back pole to accommodate a growing quilted quilt. I'm so glad I did this - and flat out refused any other type of frame. I'd already been there and done that! Frames do matter - a bunch!
2. Look at the maintenance requirements. Some require daily, weekly, semi-weekly, monthly, quarterly and annual types of cleaning routines! Whew! When do you get to quilt??? I love the HQ because I only have to add 1 drop of oil in the bobbin every other bobbin change. It's self-lubricating (or 'non-lubricating' whatever they call that)!
3. Make sure the machine doesn't LEAK oil. Many do, and ruin quilts if you forget to move it off to the side - and this also takes up quilting space on your frame so that you have to quilt smaller quilts. I like the no-oil required maintains, except for a drop on the bobbins, for this reason also.
4. Keep in mind, sometimes you get what you pay for. And also define your needs up front: business vs. self only quilting. That will make a difference. Many, many people run businesses with 16-18" machines just fine...but a 12" I wouldn't even consider...personally :)
5. Look for excellent company support with toll-free numbers and numerous supporting staff. You never want to purchase from a company that doesn't have adequate support.
6. Go to the machines Yahoo Group (they all have them) and join the groups that you are considering purchasing. You will learn all the good, the bad and the ugly. (Keep in mind, that no one will post how much they love their machines - but you'll certainly hear multitudes of complaints! Some earned, some 'user education' issues, as you'll learn!)
7. Be prepared to spend a lot of time learning the machine, all about tensions, threads, and quilting. It doesn't happen overnight, and it matters. The supplies to learn these (DVS's, books, rulers, classes, etc.) even at home, are costly. Just be prepared :)
8. Have a great time! Practice on sheets from goodwill, and when it's full, add a new top one and continue on. It'll get boring, but you'll get good. I've seen many quilters begin and they're not very good...it takes a lot of practice. Not enough practice means you'll won't get good - can't blame the machine for that :)
9. Buy the largest setup you can for your budget. Otherwise you might end up regretting it, trading it in, and loosing money in the long run. Look for the 'freebie's' that are included, as sometimes they're costly.
10. Right nows an excellant time to buy a good used machines. Lots are being sold due to budget requirements or upgrading...and the prices are down.
11. Don't underestimate the space required. It's alot! (more than my kid! LOL!)
Hope these things help you when shopping. Just a few things I kept in mind, regardless of budget, and I'm so grateful I did. They helped me to make a very smart decision. :)
Debbie in Austin