I checked out the Tama RW105 and its very good. The LEDs make it much easier to see the click in low light situations. My ideal metronome (which doesn't exist) has a lights, programmable meters, and also a numeric keypad for punching in the numbers if necessary; it would also have MIDI output so you can synch it with effects boxes..
But as been posted I suppose the best metronome is the one you don't need - your internal clock. I had a high school band conductor ( who came from the military) and he had the equivalent of perfect pitch - but for meter. He could randomly call up any meter out of his head and pretty much nail it.. so maybe there is some technique for 'remembering' exact meters - or maybe the guy was just a freak!
I use the Yamaha Clickstation. It has a backlight, a blinking click light, a numeric keypad to type in tempos and a MIDI in connection.
One of the cool features is a vibration pad to feel the tempos. This especially works for me when our singers are engaging the audience and I can get the tempo for the next song and not have the audience hear the audible click.
dc