Never played any of those two. Both too lame...^^
@Sarg0n Really? Are you joking? Nearly every master I know has played these openings! Taking into account you are much stronger than me you probably have your own point of view though.
I'd be really interested to hear opinions from people who've played both seriously about their relative characters, actually. It's easy to say "2... e6 shuts in the iight squared bishop, strategic mistake, too passive" but everyone from Capablanca to Carlsen seems to have played it at some point so it's clearly not a total patzer error. And both moves seem to offer a fairly wide array of options down the line, some of them pretty wild and some of them very slow and quiet...
ive played both in real tourneys and i prefer QDG
1e4 is best by test.
1d4 is better replied by 1...Nf6
1d4 d5 2c4 c6 3 Nc3 e6 it may be best to shut the bishop again anyway because 3...Nf6 4cxd5 might be better for White.
Kasparov has played the Queen's Gambit Declined, Tarrasch Variation, the Queen's Gambit Accepted and the Slav Defence.
Even Fischer has played the Queen's Gambit Declined against Spassky in 1972. He then probably wanted to evade preparations against his Grünfeld and King's Indian Defence.
As White I much more prefer my opponent to play the Slav. It usually becomes a slow position and I can build up an attack on the kingside that often includes my Bishop on d3 or c2 eyeing h7.
With 2.. e3 I often run into lines where enemies play b6 and Bb7 and they get counterplay. I'm much worse in these lines.
So... I love the slav! Keep bringing it :D
Are you not gonna talk about the Semi-Slav at all? Fun fact - in Bulgarian and I guess in Russian too - both openings are called "Slav defense".
As for me, I don't mind playing either of the three, but usually I go for King's Indian or Benoni against d4.
The QGD honestly makes more sense - it has a clear strategy based on freeing pawn breaks and playing in the centre. The Slav is more abstract, and I've never been that convinced by the argument that it frees the bishop, since in the opening keeping the bishop on c8 guards the queenside.
I have just played Indian stuff with Black. Asymmetric.