Just used the xdelta patch on the front page.
Now the game runs with "patch speed" enabled, so I decided to turn RTS on as well. RTS saved and loaded just fine.
Then I started to drive around a bit and noticed that the game now lags like hell. The patch basically halved my frame rate!
So to confirm that it was the patch, I went back to my unpatched rom, disabled "patch speed" and everything was smooth as butter again.
Any other SCDS1 users tried using the xdelta patch? I would really like to use RTS for this game, but not at the expense of my frame rate.
I am running a 8 GB class 4 kingston SDHC card if that matters.
(I also ran the patched rom on M3 Sakura. The game loaded, but the lag was even worse and the game eventually crashed)