Excellent quality case, properly built, with a smooth and secure action on the latches.
It appears to be built to the same standard as any professional level case, and has seen a fair amount of gigging with no damage at all (and some fairly rough handling!). I could see it lasting decades of normal use, it's that solid. In terms of extreme use, and abuse through deliberate/ignorant/lazy rough handling, it would certainly protect the RC-300 right past its own destruction, with the wooden top/bottom panels being possible weak points (particularly if thrown against pointed objects like corners of other flight cases). That said, you've got more than a busted flight case to worry about if people are abusing your gear like that!
Internally the case protects the RC-300 flawlessly during normal use, no matter what way up the case is stored, and has more than enough room for the power adaptor and a couple of medium length instrument cables.
The weight of the case is pretty reasonable, and although not particularly light, it isn't excessively heavy for the level of protection it provides.
Overall a worthy and sturdy case, very good value indeed!