I use ysmenu from m3 ninetail with v6.33 infolib.dat on my r4 rts card, but for example age of empires loads in 2 seconds but load of pokemon platinum takes about 2-3 minutes. And for example the new games, example Sonic Colours also load in 2 seconds. I can't understand this.
And no, my sd card isn't fragmented.
Anyway, I didn't like the original firmware of my card, so I looked for alternatives... I found the woodm3 which has worked on my card but new it isn't developed more, so I searched more and I found this which is work fine, and easy to update.
So if I want to play a new game which isn't work on my card any more, I have to wait a bit for the load.
But I think it isn't to bad, if I cloud use this nice firmware and play new games