I'm currently using a PhotoFast CR-5400 with 2 SanDisk Mobile Ultra 16GB microSD cards to create a 32GB MemoryStick Pro Duo card.
It is actually a lot faster than my 8GB, 2GB & 1GB SanDisk Gaming MemoryStick Pro Duo cards.
It is also faster than my 1GB, 4GB, 8GB Sony MemoryStick Pro Duo Mark2 cards.
In fact, The only MemoryStick Pro Duo cards that I have that are faster "not by much" is a 16GB Sony Memory Stick PRO-HG Duo HX & a 8GB Lexar Platinum II.
If you have any slow downs you can just replace the 2 microSD cards with 2 class 10 Transcend microSD cards inexpensively.
I doubt very seriously that you will ever see any slow downs with emulators that are caused by the speed of the card.
You might see some slow downs on games with heavy graphics like Grand Theft Auto - Vice City Stories but I've never seen that happen with mine.
I also compress my iso files to cso.
As far as having MemoryStick Pro Duo card that supports MagicGate you could always buy a cheap 1-2GB MemoryStick Pro Duo.
Typically, You only need a MemoryStick Pro Duo card that supports MagicGate for applying some themes or making a magic memory stick for modifying or unbricking your PSP.
You can also test the speed of your cards using
BlackSPEED v2 on a PSP or
Flash Memory Toolkit on a Windows PC.
I really like my PhotoFast CR-5400 & think it was a good investment, "32GB" if you would like more information on your PhotoFast CR-5400 check out this link.
http://www.photofast...ucts.asp?pid=79
It will tell you more about your PhotoFast CR-5400 & also give you an idea of whether or not your PhotoFast CR-5400 is genuine.
Spencer