I am considering the purchase of a WT 550... I sold a WT 400 a few months ago and do regret it... I am presently using a Scout Walkabout combo..the head sounds great with other cabs but falls short in the power dept.. I think the 550 will solve my problems.... I did a search and read many posts which where mostly favorable.... have they added the mute switch for tuning? Any suggestions on a good dealer... I am in NYC area Any other info will be appreciated... Thanks!!!