This is a business decision, not a technical decision.
However, that does not mean there are not valid business reasons for opening up your bug list.
And in fact I was trying to something similar last year. I was on a job site commissioning equipment. There was the company I was working for, the company that had sub contracted them and the client themselves. We reported bugs to an internal bugzilla system but didn't share that list with either the main contractor or the client. Both the client and the main contractor kept their own separate lists of bugs and would send us their lists when ever they felt like putting pressure on us. Of course all three lists had items that overlapped and items that were different, so it was a pain to try and match up all the issues and prioritize the work.
I suggested several times that if the client and main contractor had access to our bugzilla system (even for just this one project) then it would reduce extra work and confusion all around and make the start up procedure a smoother and reduce a lot of heated arguments. Of course the idea of other people seeing our dirty laundry was not acceptable.