I am an accredited beta reader at the Perfect Imagination Beta Reader Directory. Visit my beta reader profile and see if I can help you.
As a beta reader, I take fics of any status, from brand new to finished. So far I haven't turned down a single fic, so those of you desperate writers who are tiringly searching for a competent beta reader of any caliber, I'm available! You don't need to bribe me or anything, that'll just boost my ego. But, I do expect politeness on at least a casual level.
For my style, I guess I'm...funloving? Lol, I dunno. I'm sorta serious yet casual, depending on the writer I'm reading for. Umm, I think I can probably spot all the grammatical errors in a paragraph after reading it (yes, including the one I have in this section), but not those subtle grammatical rules no prose ever follows. I'm not a god, so I won't be able to perform any miracles and completely transform a piece of crap into a masterpiece. That's up to the writer. All I can do is polish and frame it. :P
As a writer, I seem to be oriented in serious works, and do not tolerate sloppy work - yes, I'm a perfectionist! I do have a sense of humor (a unique one), but my stories tend to be more serious and suspenseful than others. I personally think my literature sways towards the young-adult to adult side.
^ Ahem, please don't pay much heed to the segment above. That was what I wrote originally as a beta reader, and you can probably tell I've changed my writing style a little since then (well, at least when casualness permits). However, I still stand by what I said about preferring neater works. Yes, I'll except something that has meager grammar, but not something entirely unreadable. That's what a spell-check (with grammar option) is for-to prepare a document for the eyes of an editor.