The Logitech G15 is one impressive-looking keyboard, but honestly, it's probably overkill. I can't rate it a full on five across the board because some of its bigger features - like the LCD and the macro keys - are thoroughly underutilized. That said, it is good at its main purpose - being a keyboard. The backlighting is a nice touch too. The key feel is solid with a decent throw (not too unlike an IBM Model M, but quieter and smoother). It has a minimum of predefined keys - all media related. Next, back, stop, play/pause, and mute, along with a volume knob. All other buttons on the keyboard are either standard keys, keyboard functions, or the G keys (G1 through G18) which can be bound to any macro you want. The keys that have to do with keyboard functions are the backlight switch, the "Windows key" switch (which does come in handy), the Macro Record button, and the Memory Select - you get three sets of macros for any one application for all 18 G-keys.
It's full featured, but I don't think it's really worth the price over an equally solid keyboard minus the G-keys and the LCD. It is HUGE, after all.