The brand with the sweet spot for low cost/good stitching/good durability right now, imo, is Janome. Singer's quality declined in the 70s and hasn't really recovered, imo, and Brother makes good sergers and good industrials, but I really don't find their home machines worth taking home.

When selecting a machine, remember that some of the things that a beginner may find useful/interesting may get in your way later or prove less than beneficial later. And please don't buy by numbers of stitches or stitch functions per dollar spent... better to have a sturdy machine that is capable of making a few stitch types precisely than one with tens or hundreds of stitches that acts like it has colic.

Start with "On the purchase, care and feeding of sewing machines" here: http://www.katedicey.co.uk and http://aces.nmsu.edu/pubs/_c/c-203.pdf
http://www.dressaday.com/2008/01/how-to-choose-sewing-machine.html

if that is all you plan to do with the machine then you should be just fine. the reason for upgrading would be the size of the embriordy field but since you only want to do collars the 270 d should be just fine.

good luck and have fun.