AC powered Mutron III (original)

Any folks have any experiance with one of these boxes? I've seen 'em go for as much as $650 (?!?!) on Ebay but managed to snag one (in the mail) for less than $300. I have an original AND a re-issue but the first sux batteries and those bipolar adapters look so darn big and bulky. One with a built in supply is very exciting. I know the re-issue sounds very different with the extra juice the adapter provides......any one try the AC powered original 'Trons...? What do they sound like?