This question really is not something to be confused about.
As I have always answered (probably for the 12th times), it does not matter.
First of all, I know people in the forum, who have submitted the original who already have their visas on hand. Alternatively, I also know people, who have submitted a copy and also already have their visas on hand. So, basically, both will be acceptable.
Secondly, I always say that the part of MPNP processing is over and you would need to follow the next step. Since your documents are going to CIC, then who should you follow the most?
I, myself sent only a copy and I already had my medicals done and just waiting for the last few steps. Besides, in my case, I wanted to keep a copy of my LOA (am so close in framing it LoL).
/hth