I not only also wholeheartedly agree with making sure it is ALL right but let me tell you a short story...
I'll never forget the anguish I felt years ago when I first installed the SNS Galaxy pack. Don't get me wrong, those Galaxies to this day are awesome but there were so many things wrong with the installation files that it ruined my BC install. 
I was still a "rookie" then and failed to make a backup of my BC before I installed the SNS pack... after all, I had installed so many mods prior to that and never had any problems... why should this one be any different. I was lulled into a false sense of security. I had to, one by one, rebuild every single mod I had installed to get it back to where it was. And I didn't have any idea of how to "tweak" the mods at all at that time. I learned the "hard" way. 
Bottom line, it's much, MUCH, better to work out the kinks FIRST. Then you'll be a lot happier. The saddest thing about the SNS pack was that it was supposedly beta tested before it was released, well from my perspective it - let's just say - wasn't tested at all. I realize that for some people it may have worked but I know for a fact that TONS of us have horror stories about the problems they faced getting that pack to work properly in-game.