I am a side sleeper as well, and have all sorts of different pillows - including some crazy-expensive Tempur-Pedic ones - and the one I have stuck with the longest is a 100% mulberry silk-filled pillow. That sounds like a ridiculous luxury, but it cost less than many of the "high-end" memory foam pillows.
It's not the softest or the most plush; it's actually quite dense, but I get a great sleep with it.
Something to keep in mind is that memory foam is not all the same, is hard when it's cold, and softens up when it gets warm. It also retains heat.
I have a Snuggle-Pedic pillow and that's the warmest pillow I've ever used. It is comfortable, but I kept waking up in the middle of the night because of the heat build-up.
It took more than a week for the very strong chemical off-gassing to finish before I could even start using it, which is not something I've had happen with any other memory foam pillow. The fact that they sew it shut tells me that they don't have much confidence in their product despite claims of using clean/new foam.
It also needs to be run through the dryer frequently, as shredded foam starts to clump together since it absorbs moisture over time. I have not found that to be the case with pillows that use solid memory foam layers or memory foam noodles; only shredded foam.
I would recommend buying something that uses materials which naturally 'breathe'. Avoid synthetic materials or foam, since they trap heat and moisture. And if you are getting something with foam, I recommend that you avoid shredded foam. Oh, and never a down pillow.
That said, the second-best for me has still been a Tempur-Pedic. I have different heights and shapes and still pull them out occasionally if I'm having trouble sleeping or have specific neck/shoulder pain that benefits from the extra support.
The purple pillow certainly seems interesting though, since it uses latex foam but is ventilated and designed to keep your head away from direct contact with the foam layer, but seems very much like a love-it or hate-it design.
