I just went through the exercise. I first bought a $299 "Thermos" stainless steel grill from Target that was absolute junk, although when I paid for it, I thought it was pretty good for the money. Poor design and put together with pop rivets. A lot of the parts inside were painted steel. Took it back without even opening the box after doing quite a bit more research and looking at the floor sample more carefully.
Absolutely the best grill I found out there for the money is a $299 "PerfectGlo Pro Series" stainless grill from BJ's warehouse. I bought one and couldn't be more pleased. It's head and shoulders above any other grill I found, even up to around $600. All welded construction (no pop rivets -- OK, I found two, holding the handle onto the studs that it attaches to). Four (!) grilling burners plus a side burner -- gives lots of options for direct and indirect grilling. Individual lighters for each burner built into the valves. Includes a very heavy rotisserie (the one from Target did not and, even though it had mounting holes for one, the lid was too low to clear anything on the spit), stainless steel warming grid, cabinet below for the cylinder and other stuff. Large working surfaces on left and right (the right one's over the side burner, but I never used the one on my old grill. Cooks like a dream compared with the old Thermos cast-aluminum grill I replaced -- just as good as my friend's very expensive Ducane. Heavy stainless steel tubular burners with heavy gauge ss flame tamers (we'll see how well they hold up, but almost all of the high end ss grills use virtually identical components. The only features it doesn't have that the higher end grills have is a radiant back grill for the rotisserie, and a smoker drawer for wood chips.
What would I change? The only major thing I would prefer would be a ss cooking grid instead of the enameled cast iron one this comes with. Except for this cast iron grid, virtually everything else on it is ss (don't know what grade, but no rust after four weeks so far). The side burner is on the right, where I like to lay stuff down being right handed, but I never used the one on the old grill, so I can lay stuff on top of the cover for it. I would like a tray or hangers to keep tools. It has some very crappy little hooks for tools, but hell, I can make something better than that with all my metalworking stuff.
It isn't a $699 Ducane, but it compares very favorably with the one Home Depot sells for that price. I still can't believe that it's as good as it is for $299.