DISCLAIMER: Didn't buy these wheels from West 3D but there's so little information on these iglidur v-slot wheels in general and I want to fix that. If the lack of information on these wheels is what's preventing you from buying these I hope this review helps because they are worth trying.
These wheels have probably shown up for you before when browsing online and you're probably wondering how do these perform against delrin/POM wheels?
True to their name they are made out of IGUS's iglidur material and they feel very different to the delrin wheels. They're much slicker to the touch and have a bit of a texture to them. When they're on your carriage the difference is more apparent. The iglidur wheels run much smoother thanks to its material and I couldn't feel them bind as they rolled against my x-axis extrusion. In my experience the iglidur wheels wear more easily, at least for the first week or two of printing as they break into your extrusions and conform perfectly to them. I've also noticed that getting the tension exactly right on these wheels, you have more wiggle room just because of how easily the iglidur material breaks in and moves across the extrusion.
Well worth the money and trying at least once. I dare say the motion quality is comparable to linear rods. They are a bit pricey but they really are made from IGUS's iglidur and it's a more premium material than Delrin/POM.