I love the Sanwa MT-S. I couldn't ask for a better middle class radio in that sub $200 price range. I'll probably never use a lot of the features that are found on the radio. When I was shopping, I was looking for a transmitter comparable to my very faithful Futaba 3PM. Having choices of Sanwa compatible receivers with built-in antenna was the icing on the cake. I ultimately decided to jump on one deal that didn't include any receivers.I just rebuilt a buggy a few days ago and went with Castle and a generic Truggy can I had laying around. If I had to do it again, I would just do the castle combo. You can save a few bucks by getting an ebay non-sensored motor if you wanted to.
Radio wise, I run Sanwa, Futaba and Radiolink. My favorite is the Sanwa with the RX-482 built-in antenna. I’m not a very sophisticated driver and like the simplicity of this Tx and the absence of a tube through the body! I have the MT-S, that is their entry range.