I like ACDC more than GNR, if just because GNR only had one great album. Use your illusion was decent, and their covers were awsome(Knockin' on Heavens Door!), but they only had one great album. ACDC though, they had 4-5. Back in Black, TNT, Highway to Hell, Who Made Who, Dirty Deeds, etc. Sure, they just made the same basic album 15 times, but it never got old.
That said, I like Slash more than Angus. Angus might be the better showman, and he plays a better riff than does Slash, but it all comes down to the solo. Slash can dominate in that regard, and he does have more style than pretty much anyone alive.