I´d like to but no Paypal so far. But anyway, right now it´s basically an "Early Access" thing and I´m not a fan of such a concept (There are simply some inherent problems with it) Since Paypal is a few months down the road, I have to wait and until then and that´s fine. Right now C3 is just C2.5 because it still uses the C2 runtime, once the C3 runtime drops C3 will hopefully start to shine. I hope the C3 runtime comes out before Paypal. I will most likely switch because C3 has some stuff that I really like and I don´t mind the subscription model, not to mention I get 50% off the first year. It´s a no-brainer to at least try it for a year.
EDIT: Since I saw a bunch of people mentioning it, I also have one bigger project in development that I cannot port because of 3rd-party-plugins and I defenitely wouldn´t port it into something this early in development anyway. But it would defenitely suffice for prototyping / fooling around with ideas, that is what I mostly do apart from said big project.