Is there any reason to use G's analytics over say clicky or whatnot.
Depends on if you need it for your own sites or for clients. Hate Google all you want but shit like Clicky isn't even in the same league as Analytics. If all you're tracking is visits then you might as well use Statcounter, but if you plan on digging deep into your data nothing else comes close that I have seen. Fuck they even have cohort analysis now.