Yes well i must admit admit i have never considered Lakland before, and i have heard mixed reviews about the Warwick.
But the reviews i have read about the Fender Jazz have been pretty positive and consistent. Another thing as our set is verstile for e.g. beatles, chili's, james brown and killers, so would a Warwick be suitable for this type of music as i get the impression a fender Jazz would cater more for the required tone i would need for all these genre's.
Also some of my fav bassists i.e. Damon Minchella, Flea and Chris Wolstenholme use Fender Jazzes so if it's good enough for them it will be for me. (makes me think of the Dodgy tune now lol).