While I agree that the people at the Square Nail are very nice and it's cozy, it's also pretty expensive. A pedicure there is around $15 or so more than other places. I remember being shocked at the price. They use higher end lotions that smell and feel amazing, but the last time I went there they did my foot bath in a metal bucket, which I found off-putting. I personally found it to not be worth that extra price over all, but that is up to each person obviously.

At other places, you'll be looking at about $25 for a pedicure and then be prepared to give a tip.
I am not really too choosy about where I get a pedicure in Davis - I just want them to have the comfy massage chair and bubbly foot bath! But I just wanted to alert you to the big price difference between Square Nail and the other places in Davis Square. Sorry none of the names are coming to me at the moment.
Hope you enjoy your first pedicure!