I am reluctant to throw my hat in but, here I go. I have been a PMDG customer since the 777 for FLY2. I have bought everything they have put out since, without exception. This includes repurchasing the 737 and 777 for P3D. In all that time I have never once, that I can remember, seen them give a hard release date.
I have, however, seen them pestered, threatened, and berated during every launch for not doing so. Never, in all that time, have I ever seen it make them move any faster. In fact, what I have seen is developers, and sometimes Rob, have to come in here and basically say the same thing when that time could be better spend chasing down a memory leak of FMC logic bug. As a matter of fact, the most successful launches and updates are always the ones where they give no timeframe at all and just sneak it out. All a firm commitment does is leave people asking, "Now? ... How 'bout now? ... What about now?, " every 5 minutes, and then crash the servers when it does drop.
There is almost no one out there that is even remotely trying to achieve the realism that PMDG considers a baseline. A baseline that PMDG moves farther forward with each new product. This includes the documentation and installers and not just the core code. Part of the price we pay for that complexity is that we have to give them time. They are playing 3d chess when everyone else is playing checkers. They will get it done. As someone who almost exclusively flies the 738 and only has v4 installed, trust me, I want it just as much as you.
My two cents.
PS. Cut them a break.