I think there are several good doors. Most companies make more that one model and are priced accordingly. If it sounds really cheap, it probably is. I really like the side-mount openers. Very quiet and smooth. If you come home late it won't be the garage door opening that wakes your wife. Have never had an issue with one so don't know how they are to deal with in case of a problem.
Garage doors are pretty easy to install, easier if you have two people. Simple rules are keep the first panel level and the rails square. Neither of which is rocket science. Follow directions and plan a few cold beers when completed. Power screw guns or nut drivers make the job easier. As far as labor, the last door I installed was 16X7 door, opener included as well as take the old one out prior to starting the new door in 4-5 hours with one other helper who had done one other door prior to this one. I had done about 10 doors prior to this one including my own and helping friends with theirs. Figure a fair hourly wage and you should be close.
Yes, the torsion bars can be dangerous but if you use a good bar, (rebar about 18 inches seems to work well) and take your time it's not difficult. Make sure the bar is fully in the fitting before moving. Problems come when you have low headroom, be extra careful. From there you have to be able to count so you get the same number on doors that have more than one spring. How tight should the springs be? The rule I have used is when you stop the door part way down it should remain in the position you stopped it. You should also be able to lift the door with the pressure of one finger. In other words the door stoppage and starting should be fairly neutral. The instruction book with give you the number of turns to start with. It's not just guess work.
