Just got my 99 Classics today and am very impressed!
No need for yet another review (sound awesome, pads less so) - let's get straight on to pad rolling...
Alpha Pads
No really, they do fit
So sorry to
@MezeTeam for making your beautiful headphones look like this:
They are very easy to fit and while a little loose they will stay in place well enough to be usable.
Comfort is fantastic - way way better than the stock pads.
Sadly the sound is compromised too far for them to be viable. Bass is increased a little too far and most of the energy ("fun"?) in their stock signature has disappeared.
Brainwavz HM5 Pleather pads
This pad I believe. Not memory foam and not hybrid velours:
They aren't very easy to fit but will also stay in place well enough to be usable.
Comfort is a great improvement on the stock pads but falls some way short of the Alpha Pads.
The sound signature is definitely affected by these too, predictably falling somewhere between the stock pads and Alphas. They are certainly listenable using the HM5 pads but I have decided to go with the discomfort of the stock pads as they just sound so good.
FWIW, while the stock pads come off easily, they are quite hard work to get back on - I wouldn't want to do this too often unless Meze start selling spares.
As with many on this thread, I am really keen to be able to order the Meze approved larger pads as soon as possible!