First off I like to tell you that I got soaked into buying two of them 64mb non SONY memory cards off amazon. for my PlayStation 2. I loved them at first. but quickly found out that that they eventually lose data over time and you can never use them on 2 different PlayStation 2's or they will break.
I'll admit I barly got in 8mbs of storage, before I found out that my older PS2 memory card files no longer loaded even though they were still on the memory card. and no I don't shut off my PlayStation 2 when it is saving to the memory card.
I also heard on other forums that the same thing happen on a 128mb memory card.
So take my advice and never buy a memory card for the PS2 with more then 8mb of storage. Thankfully I got a flea market near by with cheap official PS2 memory cards. but remember this.
don't use those cheap new memory cards off amazon and especially don't buy them off ebay because their likely to not work on your PS2 because these memory cards never save again should you use them on another PS2 console.
If you do want to try one only a brand new only only. and only use them on one of your PlayStation 2 units.
anyways thanks for reading and I'd love to hear your experience in using those often cheaper non SONY PlayStation 2 memory cards