Does anyone use this lanyard?

Hello all,
I am   thinking about purchasing the following product:
iPhone Adjustable Lanyard (Neck Strap).
http://www.iphone-lanyard.com/Site/iPhone_Holder.html
I contacted the seller to ask a few questions.
They replied back telling me that the product has been sold to many blind people and it fits the otterbox deffender case and Iphone 6.
I wasalso told that the directions to put the holder and lanyard are very simple, but I should have a sighted person help me line up the parts initially.
Please, is there anyone using this lanyard?
I would like to hear your opinions about this product, how easy/difficult it is for a blind person to put it on the phone? Do I need sighted help? Is it possible to remove it easily from the phone and put it back any time without sighted help?
Thanks for your help in advance.