Regarding the reading downloaded comics thing:
I've done all the things people have mentioned: paid for them, read them online, read them in the library, read a friend's, flipped through in the store, etc.
I think all those ways (maybe with the exception of flipping through in the stores) are perfectly valid ways of evaluating any particular comics. Good God, if they weren't, nobody would try anything new. Off the top of my head, comics that I didnt buy in any form initially (mostly library browsing): Persepolis, Maus, DMZ, Invincible, Walking Dead, JSA, Runaways, and many, many others (my library kicks big-time ass) A lot of those titles, I trade-wait, and wouldnt be if I hadnt gotten them for free initially. So, I dont belittle the experience of a freebie at all.
That said, I would take the advice (and did) of someone buying Invincible over someone just browsing it in the store or online. Because theyve invested something in it. And that always means more to me. Anyone can critique, but I pay a little more attention, if someone has actually paid money for it. I mean, why should I pay money for it if the guy telling me its so great isnt willing to. Cant be that great! Conversely (for me), it makes no sense to consistently read a title, even for free, if you consistently dislike it. One or two tries is really all it takes. So in my mind, people that continue to do so are really just ammunition gathering. Maybe they just want to keep up with a favorite character, and thats fine. But I really dont listen to their opinion as much as the Paying Customer.
Notice, I'm not saying people can't have opinions, informed, uninformed, or anything in between. But I value certain opinions more than others. So yes, for me, Paying Customer's Opinion carry more weight than Freddy Freeloader's Opinion.