Two doors and air stairs have been used in BUR since... forever. No jetways at BUR. They can turn a full plane around in 20 minutes at BUR.
A few years back they came up with a rolling ramp for the nose door, though I believe they still might offer lift service (to the opposite door).
Flying into BUR, sitting in the back is like sitting in the front in terms of quick exit.
BUR terminal is a throwback to the 60's in almost every way, but still my preferred airport in LA.