Use an opto kill switch with BEC. I use this one,
http://www.valleyviewrc.com/estore/r...-shipping.html
For charging, you can use your regular charge port on a heavy duity switch. Use the signal wire as your 3.3V tap. Hang time hobbies gives details, or can sell you the parts made up already. Hangtime has tons of informaiton. They are a must read site, check them out. Basically you remove the signal wire on the plug, on the receiver side. On the charging side you use it as a tap. You then make up a charge harness using the regular servo lead plug.
I have made the transition to LIFE for all my RX packs. IT is wonderfull to not have to worry about my RX packs loosing charge over time like the NIMHs did.