For most washing I use Sears Ultra Plus with Oxyclean, boosted about 1/3 bw with STPP. This in my Neptune or Miele front loaders.
For bath towels, washable woolens, delicates, throw rugs, etc., a liquid. Lately Clorox Green Works liquid. For hand wash only woolens, Woolite for darks.
In my experience, liquids leave a softer finish but do not clean deep embedded dirt as well as a good powder. Powders can leave a harsher result but for most purposes that goes away after tumble drying.
All synthetic fabrics may wash better with a liquid. If heavily stained or with embedded dirt, though, a powder may be needed.