I got the Saitek ProFlight Yoke System for myself as a Christmas present, installed it and as far as "Is it worth it?", I can reply back with a highly qualified "YES!!". The yoke is easily mounted as is the separate throttle quadrant; You can add additional throttle quadrants for multi-engine applications if you wish, which I plan on doing in a little over a week.
The yoke setup is solid, takes a lot of abuse and responds nicely to null-zone changes in FS2004 or any other FS program you use. You also get a buttload of switches on the yoke and throttle which you can assign any darn ol' way ya like. The aesthetic feel of this yoke setup is great, and I only have two gripes: (1) The horns of the yoke are a tad thick for my tastes, and (2) Don't install the CD software if you get one or you'll have various glitches, such as midair engine outages, viewpoint changes and view swaps without your input.
My desk has the slide-out keyboard deck, which was removed so the yoke could be attached under the main deck with very short wood screws and L-brackets. This put the yoke at tummy-level, which is about where you want it. Having a real nice leather armchair helps, too!

These are my button assignments:
A1 = Parking brake. A2 = Pushback. B1 = Trim down. B2 = Trim up. Throttle detent down = Thrust reverse. T1 = Spoilers. T2 = Landing gear. T3 = Flaps up incrementally. T4 = Flaps up incrementally.
I have the rudder pedals, too, but my bad back/legs were too burdened by them. They seem fairly rugged enough.
Planes flown with this setup: Cessna 172SP, Cessna 208 Caravan, Beech 58 Baron, DeHavilland Twin Otter, DeHavilland Dash8-100, Bombardier Q400, North American B-25, Consolidated B-24 Liberator, Morane Saulnier MS500/505 (French version of the WW2 Fieseler Storch).
Anyone that wants to see my video of landing a Cessna 172 in a short grass field with the Saitek is welcome to check it out at
http://www.youtube.com/watch?v=J8OAbupDFu0