I agree. The 4r has incredible smoothness between drivers for an overall very relaxing smooth sound that doesn't lack any areas of detail across the spectrum, but they have a sort of soft sound like everything is under a pillow. I'd say the treble is better than the shure, but ironically the shure end up sounding more vibrant and interesting overall. The 4r wins if you use eq though, as they can achieve practically perfect flatness, whereas no matter how much eq you use, you can't fully recover the lost treble with the shures quality-wise".
The comfort is probably similar unless your ears are small, then i wouldn't recommend the shure as they are big enough to hurt the lobe of a small ear. The westones don't. Similar shape and fit otherwise in my opinion. The 4r are lighter as well though if that matters.
Just a question Luis have you ever actually owned either of these IEMs. Your profile does not list either as owned or having been owned. I do agree that the W4 seem to have a veil over the sound that even after amping them was still present. As for the tremble you should try the 535 reds, that is why I believe Shure produced them to overcome the shortfall in the original 535s.