My PC

Intel Quad Core Q9650 3Ghz [12Mb cache]
8Gb DDR3 RAM 1066
10,000rpm C: drive [BIAB installed on this drive]
7200rpm D: drive
GeForce 9600GT 1Gb Graphics
Asus Xonar Essence STX Sound card.

Windows 7 64bit Ultimate
Microsoft Security Essentials
Malwarebytes Pro
Windows Firewall

O&O clevercache 7
O&O defrag Pro 16
Tuneup Utilities 2010

System tweaked for best performance

I would say that the regeneration to try out different tracks as my songs is plays is around 5sec but sometimes creeps up to 9ish. Doesn't sound like much, but if I want to quickly try out new styles to find the right one it take ages.

Tested again, played my songs with one style then as it played randomly played another style. It pauses then plays the new style. This gap of no sound is averaging around 6sec but when I picked "J140_TB.STY" it took 15sec.