I wish to God that Samsung had released the Epic in the EU... not doing so was a crime imo. 
Custom ROM with lagfix makes it smooth as butter, my friend has the device and its like lightning.

Just installed 2.2 from Kies and by god my Phone is horrendously slow/nigh on impossible to use!
The lag is worse than it's ever been before!!!
Would installing the custom ROm you linked resolve these issues?
Custom ROM with lagfix makes it smooth as butter, my friend has the device and its like lightning.