First of all, is Atlas Snap-track what it sounds like...Snap it together and go. Do I need to fasten it to the surface, or will it hold itself together? Second question...I have a little bit of Katos Unitrack (the K1 set), and would like to expand it to a figure 8 with a bridge. I looked, and to do that with Unitrack it will cost over $100 for 10 peices of track. Would it be possible to use Snap-track along with my exsiting Unitrack? How easy is this given that Snap-track and unitrack have different radiuses, and lengths?