I had a big waiting list for my BEL babies just from selling on Craigslist. People were willing to pay whatever I asked for them as long as they could get one (I'm in Houston and one of the only breeders here). I'd say they're still a really popular morph. A lot of people want those pure white snakes with blue eyes. I'd bet they're probably one of the best investments if you're starting out, as Mojave and Butter/Lesser are very cheap and BEL's are easy to make and still pretty expensive.
A cool project you could get into is Mojave BEL's, and get a Mystic or Phantom to throw in there as well. Something easy like a Mojave male (Or Super Mojoave (BEL) male if you want to spend around $300+ on a male), Mojave or Butter/Lesser female, and Mystic or Phantom Female. Start out making BEL's and Mystic Potions / Purple Passions, which are two really popular combos.