Are they good?

Are they good?

Jon Snow deserves to die

What answer do you expect? What answer do you want?

Mediocre.

Im really interested in them because I like the characters but someone told me on /tv/ that GRRM books are shit

Yes, don't listen to the pretentious cunts saying they aren't.
Marketed as fuck, yes, but they are definitely worth reading.

Why are there two copies of a dance with dragons?

It is split in two volumes in some editions, like A Storm of Swords.

Why split any of them? I don't see the point other than to sell the novel twice

The first few are okay, but the series and story gets progressively worse. I think a lot of people have blinders because while the first book did chart a new direction in fantasy and subvert of the cliches that plagued the genre, the series quickly devolved. I genuinely have trouble thinking of characters who haven't either come back from the dead or had a fakeout death or even multiple fake out deaths. The whole nihilistic fantasy shtick has played itself out as well.

I think you can read the first book, then skip to the last and not really miss anything important. The overall plot is meandering because the series was originally meant to only be a few books but Martin decided to stretch it out.