The Stormy Mondays are scatter wound, with unsymmetrical coils. This gives more subtlety, especially in the top end.
I think that Seymour Duncan pickups are very well made, having taken apart several. Strangely though, I never got on with the sound of them. I have a couple of JBs I did magnet swaps to which sound pretty good. And in the neck, I like the Jazz since its good and bright. But honestly, thats it.
BKPs are still my favourite brand by far, but I also like Lollar and The Creamery. Certain DiMarzio pickups I think sound great too - the D-Activator, SDS, Area 67, ProTrack and Virtual Solo for example. DiMarzio's construction clearly seems cheaper than Duncan, but they seem to spend alot of attention on design and aim to solve guitarist's problems. Its not all roses with DiMarzio, alot of their stuff is muddy and ugly sounding.
But yeah, if you're weighing up Seth Lovers or Stormy Mondays, then I would clearly go for the Stormy Mondays.