a good buddy of mine has the Dual+ (i blame him for my e-board addiction). So i follow along when i see anything related to boosted to help him out.
The best mileage i've got on his board (on the flats) was about 5 miles. Not even in highest performance setting (Level 3 of 4). It's the only reason i didn't buy one. Anyway - i saw this youtube video and it looks pretty straight forward, but the multiple stages of run speed and the battery blinking on the controller before you are actually out of power is still annoying.
Bryang93 - you should check out some of the tutorials on making your own 18650 battery pack - it's not as scary as it seems! I might eventually do one myself, but have plenty of lipos i need to use up first before switching to home-made packs.
There was another thread on one of our ES brethren who added supplementary batteries to his boosted and got crazy range (up in BC Canada). I'll see if i can link the thread here for you.
Welcome and GL!