guitarpro needs better synth :(

[drblowthingsup]

all the music i write at the moment is on this gawdlike program by the handle of guitarpro 5, im not sure how well known it is around here but its a fantastic little thing for writing music down. however, as heawge as the sample banks are for guitars (and there are some STONKERS in there) it lacks any synthological capacity above the GM synths, which are getting dull does anyone have any ways i can get better synth sounds for it?
fanks!