In addition to what has been said above:
The Warmoth necks do seem to have a lot more about their construction, in that they are steel bar reinforced with two way truss rods etc. As a result they're apparently quite heavy, so bear that in mind!
I've got an Allparts Jazz neck on my Precision bass, very nice, pretty skinny, thinner at the nut than my Fender US Jazz. But a perfect fit into the neck pocket of the Encore body!
Si