The DBXL is just to heavy and the 4wd is extra load for Brushless, I tried it with a LOsi 5ive and run times were just not enough. In the Baja I run 2 x 4s 8000mah and get 30 mins run time and quicker than most petrol. You do need to adjust driving style though and think about conserving energy a bit, backing off on the throttle early on a good straight and letting it coast to the corner saves battery and gives a much better line into the corner at the same time, I wouldn't go back to petrol now I find I just get to use the Brushless far more with it being quieter so I can use it anywhere
At some point I want to build a short brushless Baja and shave some weight off
8s lipo's are still pretty rare I think, options with 4s are far better but 5000mah 4s are a waste of time for sure