I bought the MRC Prodigy system a year ago and have installed decoders in 8 diesel locomotives and use two tethered controls.
Operating likes: The hand held throttles are just fine. You dial up your engine number, press the forward or backward button and off you go. The throttle knob is smooth with plenty of travel. Building and tearing down consists is a sinch. The emergency stop everything button is great too.
Operating dislikes: mmmmmm, nothing to compare it to - beats my past experience with DC. Several buttons on the controller for additional functions but no stock decoders that use them.
Programming likes: simple push button programming - top voltage for example, dial the throttle to a position proportionate to your top voltage then hit the top voltage button, very simple. Reverse polarity is great - you can do back to back consists, etc.
Programming dislikes: two digit addressing - we use the last two digits on some locos, the first digit on another loco, etc. If you neared the max on the number of possible locos (32) you'd be in trouble unless you re-numbered everything. (I have more, I won't ramble.)
Decoders - buy the right ones and good luck figuring out what you'll be getting. Skip the 305s and be sure to get the 315s. Beware of plug problems as well. I want 8 pin plugs and have received 9 pin-plug for the decoder, not for the loco units. I complained and MRC sent me plugs that I soldered (not without great difficulty and problems running). My one LENZ decoder does not respond to MRC's push button programming for max voltage, momentum, etc.
Overall though, great value - I've got less than $300 into it with all the decoders and we still manage to have a great time.