I received more hand/finger injuries from my R-10 than any other tool I have owned

and I have been in construction all my life

This cart bites
That's one thing you do not want...hand injuries to a keyboard player means no work, or at the very least, pain while working.
I've never used a cart...everything is light enough to carry comfortably, and I don't mind making a few trips out to the car. I certainly wouldn't schedule my gigs that close together where I'd be rushing to get set up.
Life is meant to be sipped...not gulped.
Ian
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Yamaha Tyros4, Yamaha MS-60S Powered Monitors(2), Yamaha CS-01, Yamaha TQ-5, Yamaha PSR-S775.