Not going to argue with success. Go bigger. However, might be more hum and certainly more power draw.
http://cgi.ebay.com/Isolation-Noise-Suppressing-Transformer-5kVA-NEW_W0QQitemZ310306755784QQ
http://cgi.ebay.com/Isolation-Noise-Suppressing-Transformer-5kVA-NEW_W0QQitemZ310306755784QQ