I personally like Hitec RX and Servos. The prices are good, and the stuff has proven to be durable for the most part.

HS-81 servos can be prone to bad pots if you use them in high-vibration set ups though.

There are a lot of options out there though.

If you order a Hitec, just make sure it's the Futaba/Hitec compatiable version, not the JR compatible version.

The 04something single conversion RX is good. The Feather is to be avoided. The 555 and Electron6 duel conversion RX's are good (I think I currently have a total of something like 16 combat RX's Most of them are Hitec 555's and Electron 6's. I have a handful of FMA extreme 4's, which are very good, but not as durable as Hitec, and 1 Polk Seeker 6, which is nice in that it's crystal-less, but it's durability is questionable, and there have been reports of spotty QA with Polk gear, some are DOA or act funky.