RE: Is a balancer required or recommended?
You can use the LiPo with out the balancer for a little while. I have been using mine for a few months now but very casually. It is very recommended for battery life and performance that you get a balancer. One that I hear about frequently is the [link=http://www.astroflight.com/store/store-type-tem.html?item=products:af-106&sid=0001TuHQF6Ps598bCU661C6]Astro Blinky[/link]. It is relatively inexpensive and will lengthen you batteries life.
So the short answer is no they are not required but rather strongly recommended