works great! Some tips:
I have mine for more than 6 months now. It works great still. The manual says it doesn't work with 4gb cards but mine does. My 4gb is a SD card from Transcend, the hi-speed model. I did not try putting 2 x 4gb ones, since I don't have another. For some time I thought it was showing problems since it didn't work every time, but I found out that I was the culprit. When I put my PSP in its case, sometimes the cable would be pushed and then the adapter was released. It was just a matter of pushing it in properly again. Make sure yours is not loose when picking up your psp!

It did not work...
I don't know if this is true for all the units but for me it did not work. I think it's choosing the type of memory card you use. At first, I used a 256mb sd card. It worked but the next time I opened it, it did not anymore. But it can read a dual voltage MMC, like the ones used by Nokia cellphones but the B slot doesn't work even with the A slot working. I guess the connector is still isn't that stable. So it looses connection. This unit should be put back in the drawing board.

Memory Card Support
İt does not support memory sticks greater than 2 gb. I bought it to use 2 x 4 gb memory card at the same time but I do not use it. I think Play-asia must add some comments about this case.

So Dont buy it , if you want to use 4b or more..

Does not work on My PSP (1004)
I tried it on my PSP and it doesn't work on it (with firmware m33 3.51). I tried to flash it with another custom firmware version but nothing changed (3.40* LE).

But the device works on some PSP. I tried it on another and it works.

Does someone knows my it doesn't work on my device?

Some guesswork required
The first convertor of this type that I ordered worked out-of-the-box with my unformatted SD cards, which I thought was great, so I went about transferring files from my Mem Stick Duo to PC, and then back again to the SDs... when the entire unit ceased to function. After powering down the PSP for a while, the cards briefly began to be detected again, then died a second time - I was quite distraught.

A replacement was sent to me, at which point I made sure the VERY FIRST THING I did was format the 2 SD cards I was using - and I've been enjoying it ever since. So despite the indication that your unformatted card is detected, just be sure to format it for PSP before moving ANY DATA across a usb connection, and you should be fine with this product.