I don't have one, but I occasionally use one that my neighbor has. In terms of quality, it's very nice. Nothing has gone wrong with it, the 6.5 hp GCV190 starts easy everytime, the variable SP works just fine.
But I don't like it. It's got that Xenoy (resin) deck. It's SUPER light. So light, in fact, that it almost feels like a toy. It tends to bounce around on the lawn (no weight to it), and it feels like there's little substance. Again, it's a very high quality mower, but I just don't like how it feels.
It's like a car where you just can't get the driving position JUST right, between the wheel, seat, and pedals. Objectively, it's an excellent mower, but it just doesn't feel quite right using it.