This is a pretty helpful document to help folks understand what's really common. Unfortunately, while it's nice to see a 1x liquidation preference, when multiple rounds happen these often turn nasty as each investor starts to look out for themselves in the pile. Unfortunately, the entrepreneur is usually a loser in that scenario unless the exit is at a nice valuation. A great argument why an up-round isn't always a good thing.
I find it hard to believe that anyone would accept a multiple liquidation preference. I'd seriously consider it better to shut down than to stay in the game for the benefit of investors I'd end up hating.
I can't even imagine MLP benefiting investors. It'd be a huge morale-buster. Also, a company that needs to accept those sorts of terms is in severe trouble and, as I'd see it, although I may be wrong, not likely to be a good investment at all.