Well, if your arranger has one, there's always the manual, and the forum...
But, like I said, arranger use is usually about improv, requests, and drop of a hat song lists. A slow sample load time can only hinder this. Basically, you are forced to pre-load what you THINK you might need at the start (and the T2 takes HOURS to fully load the sampler if maxxed out). Even just a nice 64MB piano set is probably 5-6 minutes alone, and the RAM can go to 512MB or more. Do the math...
It's OK if you just play alone at home, and have time to burn (or take a shower!), but put an audience around you, and no-one is going to wait ten minutes for a song (while your keyboard is DEAD!). The arranger player's mentality about arranger features is "I want it ALL... and I want it NOW!" (Thank you, Freddy Mercury!)
If I can't have it NOW, I don't want it...!