Both, and...

My camera is pretty close to my ideal. The state of the camera is set with the knob, shooting options are toggled with buttons, and the more obscure settings are reached by menu. For convenience, a number of items can be accessed in more than one way.

With a knob, I can choose manual, aperture or shutter priority, program or full automatic exposure modes, replay mode, movie mode, the setup menu and white balance, ISO and quality/resolution settings directly. There is a thumb wheel below to select the settings in each. Very direct and efficient way to change the state of the camera before the shoot or as needed when conditions change during a shoot.

Critical shooting functions can be instantly changed by the buttons. There is a button to toggle between auto and manual focus, infinity and macro settings. Another toggles through no overlay on the monitor, live histogram, grid-screen or full information. Another button does double duty, setting the timer to 3 or 10 seconds, or deletes images when in review mode. The button above that lets you see either a quick quarter screen or full screen review of the last shot without switching the state of the camera into review mode. Then there is the menu button and at the top, the zoom control and auto exposure/auto focus lock buttons. There is a second zoom rocker and a vertical shutter release on the optional battery pack. The camera is thus as comfortable for vertical shots as for horizontal.

There are three other buttons behind the shutter release, which is also surrounded by the on/off switch. First is an assignable function key, that I use to toggle between aperture and shutter speed when shooting manually, which is quite often. Its function can be quickly changed in the setup-menu. In the middle is the flash mode selection button, and on the right, the exposure compensation button. Finally there is a button for illuminating the camera status readout on top of the camera. The readout pretty much describes the state of the camera.

The opening page of the menu is completely user configurable. Any six menu items can be assigned to the page to suit your individual way of working. I rarely need to use the rest of the pages.

As I mentioned, there is a good deal of redundancy - one can set white balance, ISO or resolution/quality either with the knob or the menu button. The thumb wheel and rocker are also redundant for many settings, so it gives you a choice of how you want to work. The controls are convenient and as logical as possible.

It is a vast improvement over previous cameras, and I find it supremely efficient. Working in very low light, I can quickly and positively make adjustments to the camera during a shoot, even if I can barely see it. I really don't see how they could be much improved.