This is a quality field for a mid-Janurary race on US soil. As far as I can tell all of these guys are sub 4 milers. This is a race Webb should win, but make no mistake about it, it will not be a cakewalk becasue class B guys always want to run fast times to secure contracts or to hold onto them. A field of elites would be most interested in just winning at this time of the year.
With that said, this race s/b fairly fast and if the race is honest, it should be won in about 3:55.
Also, in reference to Webbs schedule, racing a mile every other week is not going to kill you. A couple of decades ago, our top milers use to race practically every weekend in a host of US televised meets like the Philadelphia Classic and Sunkist Invitational, etc.