I concur with this advice 100%. In my opinion, a separate BEC is necessary. Weight is an issue, but is something best considered in the initial planning stages of any particular model to be built.
I like your work. You have put a lot of thought and effort into your model and it shows.
Originally Posted by T3chDad
I would use a separate BEC. Even though the retract servos won't be used that often, they have the potential to have the most current draw. I wouldn't want to hit my retract switch and then have a brown-out as a result. Better safe than sorry after all the hard work you've put into it. It's definitely worth the $20-30 for peace of mind IMO...