Easy to use, sew buttons, and button holes

This was bought to replace some old Singer machines that had were giving trouble.  Compared to the Singer, it is extremely easy to thread, and the automatic needle threader makes life very easy!  I'm not a sewer, but my mother and aunt are, and they love this machine.
I have used it to sew on buttons - one of its best features!  It's a one-step automatic buttonholer, and by putting in the button in the holder, you get perfect sized buttonhole all the time.  The only problem is correctly setting the stitch length/width, thread tension etc. for the fabric.  This requires a bit of trial and error so practice on a piece of scrap cloth first.
I have only used the button-sewing and buttonhole quick change feet; the other feet are zipper, narrow-hemmer and blind-stitch.  It also comes with twin needles which I plan to try out sometime.  A neat feature is the thread cutter which cuts the thread to the right length so you don't cut the thread too short or too long.
The dimensions of the machine are 12-1/4 by 7-3/4 by 9-3/5 inches, and it weighs only about 11 lbs!!!  It has built in storage and also can convert to a free arm sewing machine for sewing cuffs etc.  There are 26 built in stitches - heirloom, decorative, stretch, and blind hem.
I suspect it won't stitch very thick material, like denim, very well, based on my experience with stitching doubled over fabric.
I've found that sometimes the bottom thread "bundles" up underneath, not sure why that happens, but it may be due to incorrect stitch settings for the fabric since adjusting the settings usually results in it stopping "bundling".