Apparently the best may to improve the trigger is an M3 8mm bolt something I am going to investigate when I have had a few more pellets through this one. Your girlfriend is right, the trigger is not nice and a very long pull. That said it is usable and it does group well doesn't it?
When you think of it shooting straight out of the box, unfettled, they are not so bad a gun. Even HWs require attention, thats why SFS make so much money!