bleeding brakes

[Gent Matthew-EMG030 <Matthew_Gent-EMG030@email.mot.com>]

I'm in the market for a brake bleeder.  I'm tired of doing it the two-person
manual way.  I've heard of 3 types:

1-air pressure on top of the m/c forces it through      
2-hand pump sucks from each individual line     
3-check valve on individual line allows one person to pump the pedal

What are the advantages and disadvantages of each?  Which is most popular?

Thanks,
Matt