I'm going to end up ordering the 510, and started looking at recommended sites. Seems like many carry only black or are out of other colors. My wife wants white and I really had a hard time finding it for a good price. Finally went to healthcabin.net and they had it, along with very good prices. No free or $5 shipping (they are in China, so no surprise there), but the prices are low enough ($35 for the standard kit and $18.50 for a PCC) that even with the $15 shipping it's a really good deal.