I have gotten emails from some Audiogon members stating that they got good results using Shelter cartridges on their WB arms. The WB arms have stabilizers, and should do better than basic unipivots with a lower compliance cartridge. I think you're reasonably safe with the Shelter or Koetsu or WB cartridges. I don't have any experience with the Allearts cartridge.
As far as the cartridge choice goes, that is pretty subjective, and may have budgetary considerations. I think the Shelter 901 is a terrific cartridge and costs far less than any of the other ones you mentioned. If you want to venture into higher-priced territory than that, I would use the Shelter as a benchmark, and audition the others against that, to see if they can beat the Shelter enough to make them worth the extra money. I think you'll find that the Shelter will "hold its own" against just about anything, and is alot easier on the wallet. But, if you find that you like one of the others better, and want to fork over the dough, then at least you've satisfied yourself that you got more for your money by comparing against the high-value cartridge. I've seen people get a little upset when they have bought a very expensive cartridge, and found that the Shelter would have done better for alot less.
I would also add a ZYX R-100 Fuji to your cartridge list. This is a very fine cartridge, about $2k, and is competitive with the Shelter 901. The Fuji is slightly better on small-scale music and the Shelter is slightly better on large-scale music, and the bass response on the Shelter is absolutely first class.
As far as the cartridge choice goes, that is pretty subjective, and may have budgetary considerations. I think the Shelter 901 is a terrific cartridge and costs far less than any of the other ones you mentioned. If you want to venture into higher-priced territory than that, I would use the Shelter as a benchmark, and audition the others against that, to see if they can beat the Shelter enough to make them worth the extra money. I think you'll find that the Shelter will "hold its own" against just about anything, and is alot easier on the wallet. But, if you find that you like one of the others better, and want to fork over the dough, then at least you've satisfied yourself that you got more for your money by comparing against the high-value cartridge. I've seen people get a little upset when they have bought a very expensive cartridge, and found that the Shelter would have done better for alot less.
I would also add a ZYX R-100 Fuji to your cartridge list. This is a very fine cartridge, about $2k, and is competitive with the Shelter 901. The Fuji is slightly better on small-scale music and the Shelter is slightly better on large-scale music, and the bass response on the Shelter is absolutely first class.