I honestly think Nebraska 9 stage 2 ban MDSR is the way to go. Yoshi's Brawl has too many elements that annoy too many players, even though it's got nice medium attributes all around.
So I'm going to break down possible Bo5 scenarios to see what effect MDSR can really have when it's in effect.
In these scenarios, out of 9 stages, assume 1/2/8/9 are the counterpicks, and are the ones always being banned to shorten things a bit. Obviously not true for most matchups but that doesn't really matter for what I'm trying to show here.
Player A and Player B, stages 3/4/5/6/7
ABAB_
Strike to 5, A wins
B wins on his CP, 3
A wins on his CP, 7
B wins on his CP, 4
A can choose between 3 (lost on before), 4 (lost on before), 5 (won on before), 6 (previously unplayed), or 1/2 (stages he bans against B, previously unplayed)
ABBA_
Strike to 5, A wins
B wins on his CP, 3
B wins on A's CP, 7
A wins on his CP, 6
B can choose between 3 (won on before), 4 (previously unplayed), 5 (lost on before), 6 (lost on before), or 8/9 (stages he bans against A, previously unplayed)
AABB_
Strike to 5, A wins
A wins on B's CP, 3
B wins on his CP, 4
B wins on A's CP, 7
A can choose between 4 (lost on before), 5 (won on before), 6 (previously unplayed), 7 (lost on before), or 1/2 (stages he bans against B, previously unplayed)
So then you can also have 3 cases where it's reversed so we've effectively already counted those and the letters are just reversed (BABA, BAAB, and BBAA).
In each scenario, the counter picking player can choose between 2 stages he's previously lost on, 1 stage he's won on before, 2 stages he bans against his opponent, and one untouched stage.
The thing I find most interesting about MDSR is that the stage that opens up 4 out of 6 times is the stage from game 1, which was already selected through starter striking and will be the closest thing to a neutral stage (hypothetically). The other 2 out of 6 cases (ABBA and BAAB) the stage that opens up is a counterpick you've previously won on. However this progression requires you to win on your opponent's counterpick during the set.
But wait there's more
So those are the Game 5 scenarios but one of those also has a hidden MDSR previously, and that's AAB_ (or BBA_)
AAB_
Strike to 5, A wins
A wins on B's CP, 3
B wins on his CP, 4
A can choose between 4 (lost on before), 5 (won on before), 6 (previously unplayed), 7 (previously unplayed), or 1/2 (stages he bans against B, previously unplayed).
What's interesting here is that while he doesn't have his two best stages (8 or 9), A is in a really good spot since the stage he previously won on, and is not allowed to CP, is a stage that's supposedly in B's favour. The DSR rule here is stopping him from returning to a stage that, while he did win on it before, should hypothetically be B's stage! Rather than blocking a stage where A is meant to be advantaged on (and he previously won on), it's blocking B's stage. This means that there's (hypothetically) another stage that is open that's also in his favour.
So there you have a rough idea of the effect of MDSR. For some reason. Probably reads like a jumbled mess so I'm sorry if no one can follow this. I was pretty much just spitting my ideas out unfiltered.
TLDR: There are 8 situations where MDSR takes effect.
2 out of 8: The most beneficial one for the CPer takes place in a set where that CPer has already won a game on his opponent's counterpick.
6 out of 8 (including the 2/8 above): The "unbanned" stage from game 1 has already been filtered by the starter stage selection process.