Roland V-Synth XT features a PC card slot for flash memory expansion. Roland web site only lists small sized Compact Flash compatible cards that are not available on the market any more. We recently done some tests and identified 2 cards that definitely work with our V-Synth XT.
Out of 10 different card only byteStore 1Gb and SanDisk Utlra 2Gb (up to 15MB/s 100x) cards successfully worked.
So, it shows that buying a Compact Flash cards for your Roland V-Synth XT is quite a hit-and-miss game. Actually more miss then hit. As a result we recommend you to stick with these two. Both of them are available at UK Amazon web site at the moment.
To be honest 1 Gb Compact Flash card is more then enough to store tones of Roland V-Synth XT project. 2 Gb card gives even more space. It looks like trying to use 4 GB card is an expensive overkill. It would be more secure to get two identical cards and take a back from one to another from time to time then to get unnecessary double sized card.