RE: Aerobird 3 battery question
Most people just buy Deans connectors and solder them on the plane. Deans connectors are the industry standard for most lipo's. Proprietary brands like "Parkzone" and others use their own connector in hopes you will buy their more expensive replacement batteries instead of other brands.
I have had great success buying from Hobbycity. Anything in stock usually arrives within a week or so. Just don't order anything that shows out of stock or shows a negative inventory or you may be waiting a few weeks for your item.