Just wanted to post a picture of my viv, I use tile, and have a sand box for my dragon that she has never touched besides the occasional walk through when exploring. I wouldn't recommend using sand for the whole tank ever, my only purpose for having that in there is for when Thil goes gravid, I will hopefully have a heads up. The tile is wonderful, though she isn't on it much and usually hangs out up top but it really does wonders for their nails and its easy to clean.
http://sphotos.ak.fbcdn.net/hphotos-ak-ash2/hs181.ash2/44470_10150253584650529_673520528_14234521_6059164_n.jpg
different picture in link.
http://sphotos.ak.fbcdn.net/hphotos-ak-ash2/hs181.ash2/44470_10150253584650529_673520528_14234521_6059164_n.jpg
different picture in link.