I love my office chair on wheels. I requested it as a Christmas gift a year ago. My sewing room is carpteted and it is easier to scoot back than a regular chair. I like the support it offers, and sometimes I raise or lower the seat to change the angle of my knee on the foot pedal. However, I second the "no arms" style. Mine has arms that continually hit against the sewing table.
Another thing I try for tight neck and shoulders is heating up a "rice" neck bag in the microwave and laying it around my neck. You can buy these with a variety of stuffings (corn, buckwheat hulls, etc.) and heat them for about 2 minutes (varies by microwave). Mine stays warm for about 20 minutes and helps loosen up the muscles. Or asking DH to rub my shoulders helps also. (You can make your own "rice" bags...I did them for Christmas gifts last year for friends and they went over very well.)