I've got a Yorkville XM200T combo (2 x 10", 200w) that I'm hoping will cut it with a new, gigging rock/hard-rock band I just joined. Luckily, there is only one guitarist (with a Randall half-stack). Simple question: will my amp be loud enough? The store I bought it from will let me upgrade to an XS400T (400w 2x10) for about $400 more, or would I be better off spending the money on an additional cabinet for my existing amp? BAss gurus, let me know what you think!!