Tarrasch or Grunfeld

If you were to going to put in time, learning  defence to 1d4 1Nf3 1c4 flank setups which would you choose of the 2 ? Tarrasch or Grunfeld and some reasoning for your choice.

Thank You, 

Begrudgingly the Tarrasch.  I at least understand how to play IQP positions, being one that plays the French and playing in many positions where White (Exchange w/ 4.c4) and Black (Open Tarrasch w/ 4...exd5) deal with the IQP.

I hate the Grunfeld like the plague.  Black, White, doesn't matter.  Not saying it is unsound.  It just does not click at all with my way of thinking.  I avoid it at all cost with both colors! 

But what I think is not what others, like Kasparov, think.  The point being that what others think won't really help you!  YOU need to figure out you!

For me, It's the Sokolsky, French, and Dutch that make up the core of my repertoire.  For you, it is likely completely different!

I could probably appreciate either opening . I personally don't find one more exciting than the other. I have put about every defence on the board throughout my playing years...sometimes I think complexity is the way to go (Grunfeld) ...sometimes I think technical is the way to proceed (Tarrasch) . I guess I just wonder if others think some fight exists in the Tarrasch ? Or is it to much of a fixed move opening ? I think there might be enough flexibility with the old main line (9...dc) and new main line (9...c4), the Swedish and HS Gambit and possibly a few others to keep clubmates on thier toes  but  is to much energy required with this approach ? And do all you all think the Tarrasch is completely sound? Thank You for the insights shared so far!

I prefer the Tarrasch Defense. I'm big on king safety and found that my king never faces an attack when playing it, which is quite unusual for black defenses and I wish I could find such a defense against 1 e4. I've noticed that many of my Tarrasch Defense games eventually become endgames of only two rooks with pawns vs two rooks with pawns.

I once read somewhere that even if you lose the IQP there is a reasonable chance of holding the endgames about half the time due to pawn structure and piece activity. That has seemed to be the case to me I think. I had a game recently against a slightly higher rated opponent in which I lost my IQP in the endgame. When he won the pawn a rook trade occurred and he was left with a rook, bishop, and 4 pawns all on the kingside, I was left with a rook, knight, and 3 pawns all on the kingside. He didn't manage to find a way to convert it. 

One other thing I've found useful for me is that my 1 c4 opponents almost always choose to transpose to the Tarrasch Defense at some point. 

I use the repertoire book from 2019 titled Fight 1 d4 With The Tarrasch by Vassiloios Kotronias. After 1 d4 d5 It also covers moves white plays instead of 2 c4.  

The Grunfeld is considered better but I consider the Tarrasch more practical.

The vast majority of the time, those 4-on-3 R+P endings, the side with 3, assuming we are talking efgh vs fgh, the side with 3 (let's assume Black) should set their pawns, if possible, on f7-g6-h5.  If the f-pawn has advanced, the defense is a LOT more difficult, if possible at all!

Both the Tarrasch and the Grünfeld are good openings, but hard to play correctly.
For the Tarrasch study some games by the young Kasparov:
https://www.chessgames.com/perl/chessgame?gid=1070105

For the Grünfeld study some games by Maxime Vachier-Lagrave:
https://www.chessgames.com/perl/chessgame?gid=1604383 

Both are strong --it's not bad to have 2 defenses. I've played the Tarrasch for a while now and like it. (But in blitz I'll play lots of other defenses too and I'm starting to learn the Dutch now.) Starting by learning how to defend in IQP endgame  and the 4vs 3 endgame when it;s lost is a great suggestion. The famous game Flohr-Capablanca is where most begin. It is scarce as hens teeth but if you can find Baburin's book 'Winning pawn structures' it is pure gold. If you read German there are 2 excellent books on the Tarrasch. In English Aagaard has 2 books on it, Schiller has one [his best book], Bezgodov has one, Collins has one and so does Kotronias. I think they are all really good.  But Gruenfeld is terrific too-you need to play over some games in both and  see which MG positions you would like to be in. - Bill