Should I be afraid of the Slav Tolush-Geller Gambit? As Black, after 1. d4 d5 2. c4 c6 3. Nf3 Nf6 4. Nc3, I like to play 4... dxc4 5. a4 Bf5, but I am afraid to play 4... dxc4 because of 5. e4, the Tolush-Geller Gambit (always followed by  5... b5 6. e5 Nd5 7. a4 e6)

  [StartPly "9"]

  [FEN ""]
  1. d4 d5 2. c4 c6 3. Nf3 Nf6 4. Nc3 dxc4 5. e4 b5 6. e5 Nd5 7. a4 e6 (5. a4 Bf5)


I am a 1800 Elo player who likes quiet and strategic positions, so this gambit which leads to insanely sharp tactical positions is frightening me...

But is this gambit really sound?
Does it really give White enough compensation for the sacrificed Pawn?
Should I really be afraid of it?
Should I really abandon 4... dxc4 because of this gambit and choose something else instead (maybe 4... a6 the Chebanenko)?
It is quite sound in my opinion. As White I always welcome dc: Black surrenders the center, and asserting a control over it is well worth the pawn. I am not so much sure about 6. e5 though.