-Trinitron-

What is the purpose and which one is better. What should I look for to boost a b16 or does it matter?

STHPERFORMANCE

360 degree thrust bearing is better.... Thats about all i know.

SpoolnG2

360 degree is better, b/c it protects the entire shaft, and not just part of it. it is better especially when boosting higher numbers b/c its more stable.

-Trinitron-

So if a turbo is not advertised as having a 360, should it be assumed that it is a 270?

SpoolnG2

yeah, most likely. usually a 360 degree thrust bearing is an option which costs a little more money.

boosted hybrid

It transmits the thrust force equally onto the compressor/turbine shaft. At high psi levels the thrust force increase expotentially, so the force isnt transmitted equally giving a expotentially increased wear of the center section.