I didn't write that specific review but here are some of my thoughts on reviewing headphones.
I have the Sennheisers at home and use these as a ref for other "similar" kinds of headphones.
When listening to in ear types I naturally have the original (uncomfortable and thin sounding) type and have some Better quality yet affordable in ear types.
It would be unfair in my opinion to compare almost any in ear to the 650's, but then in ears are a whole lot more portable.