I know people have different opinions on Facebook games and the whole model of paying to advance and what not, but I have been in this beta for a few weeks now and it seems decent enough. Very Pokemon-esque. Plus I have faith that Insomniac knows what they are doing. They have done a pretty good job at releasing great games over the years.
So if anyone is interested in trying this game out, I have one key left I can share, just PM me and I'll send you one ASAP.