Dekoni Audio - Choice Earpads for Beyerdynamic DT Series Headphones

Alright, received my pads today and I tried them on my Beyerdynamic Custom One Pro Plus (same fit as DT series)

For context, I've listened to the music on these headphoness for about 7 years now, they're working flawlessly. I've used their included pleather pads as well as ordering replacement pads but this time they were velour (which I've been using for the past year and a half)
I wanted to go for something that's more comfortable and I kinda missed the pleather ones because they had the boosted bass to it and what's better than the original ones? Dekoni ofc!
Little did I know that I wouldn't like these pads but that's not a fault of the pads, these are hands down the most comfortable ear pads I've owned and felt, and it's not like they don't deserve your consideration, they really do. I'd pick them over the original Beyer's leather pads any day. But having said that, my issue with these is the sound that they changed, and boy was that a dramatic change.
I think velour ones kinda gave me the taste of the openness of the sound coming from your headphones since it's easier for the sound to escape through the pads than it is on leather/pleather ones.
And once you get a taste of how much more enjoyable that audio sounds, there's no going back. So immediately after putting these pads on and listening to music, everything sounded so much more muffled and muddied. I put my sliders down for the bass (a feature on Custom series of headphones), but that doesn't really help the soundstage, now you're compromising on the bass anyway that you wanted to boost in the first place. But that little boost to the bass in my opinion is NOT AT ALL worth it when you have to compromise on the soundstage and the openness of the music.
Things sound more lively with velour pads because in a closed back headphones like mine, that's all the help you can get, you can't just turn the headphones into open-back ones.

This brings me to the next point: I do think that these earpads are worth it if you're replacing from one leather pair (like the original ones) to another and if you want to maximize isolation and you don't mind the somewhat extra muddiness of your sound when you're putting them on a pair of closed-back headphones. But I do imagine that if you already have a pair of open-back ones like DT 990 PRO or DT 1990 Pro etc. then these may be a much more viable option since you're not closing off the whole space for the sound with them.

So I would give these earpads a 5/5 for what they're meant to be: extremely comfortable, premium feeling, great isolation, boosting some bass when you need it
But I would definitely say that they're more a situational choice and going for them depends on the individual.
I'm keeping these for my next purchase of DT 1990 Pro whenever that may be, till then I'll take them off and keep using my velour pads on my Custom One Pro and when I have some extra cash later on, I'll try getting Dekoni's Choice Suede for my cans instead.

TL;DR: Great pads in terms of comfort but they come at the cost of decreasing sound-stage especially in closed-back headphones, so do what you will with that information.

Good for closed back headphones but stock velour pads are preferred for the open back ones.

Fits perfect on the MMX 300 (Gen2). Better at isolating ambient sound that the stock earpads. Sound is just as good (for casual use). The real test will be how much wear & tear there is after a year or so. I expect these to last several years to be worth the price.