I had a very inexpensive Brother CS6000i that is a good machine with 60 different stitches. My niece and nephew own it now, and despite their youthful enthusiasm and experimental tendencies the machine is going strong after being in their "care" for over a year. Periodically they abuse it enough that it errors out and stops but they've discovered if they turn it off for a few hours it'll self-correct when they turn it back on. My sister tells me they've even sewn through cardboard with it. Amazing. For an inexpensive modern plastic machine it's a pretty good workhorse!
My only gripe with it was its size (too small to quilt large quilts) and that it's so light it tends to scoot away unless you have some grippy mat stuff underneath. But other than that it served me well as my primary quilting machine, I quilted an oversized twin in it, no problem, and for piecing it was great. I'd still have it except that I wanted to encourage my niece and nephew to sew.
They sell on Amazon for around $140-150. It comes with an extension table and a quarter-inch foot (and a bunch of other feet), and it has a needle up/down button. The case is the kind that's just a cover, but it is a hard shell and the built-in handle on the machine itself makes it very easy to port around.