Liquid detergents: HE vs. regular liquid detergent. Which is better?

The main distinguishing factors of HE soaps are that they are more concentrated, so don't need to use as much detergent.  Also, they are specially formulated so that they do not create the same level of suds as regular detergent.

The Washer Fan team's analysis:

• Do not use anything other than liquid HE soap in a HE washer. It is less expensive per use, and you'll find that you get more loads per bottle than regular soap. 
• Only use 1-2 tablespoons of liquid HE detergent in a HE washer; this is the equivalent to 1/8th of the laundry cap's full volume.

Surprisingly, no more detergent is needed to produce a clean and fresh-smelling wash than the amount recommended above.