I have some ER4Ps that block out sound very well. I cannot hear anything at all. However these IEMs are very pricey for most. I have other earphones that are a lot cheaper to avoid having to throw down so much cash in a set of headphones or IEMs. I have some ATH-M50s, HE Re0, Shure Se215, Brainwavz Betas and Senn H120s. All have suited me well though each one were a bit pricey or cheap.
I am tempted to jump on the R1s though I am curious how these compare to the HE RE0s.