Hendrix has quite a resume. I first noticed him on Billy Harper dates on youtube. He has also played in Charles Tolliver's big band and a host of other credits. Sounds good to me when I hear him, though I've never sought him out. Williams has been around for 25-30 years, and I see him pop up in credits from time to time, but he's never caught my ear, good or bad. Both have a lot of academic credentials (as do so many jazz musicians these days).