If you have the coin I would buy a factory spit with both edges. Having the inside metal edge is nice when it's icy, and, in my opinion helps in ski mode. But, I also have a do it yourself that works just fine... it just lacks one edge (but rides better in the pow because I loved that board before I cut it in half).
They are great for flats if you are comfortable skiing a little. You will quickly become proficient in the splitboard "power pie," because as you said converting all the time from snowboard to split is a pain (and can take a little time until you get good at it)... and I find that the more you take your skins off and on the more likely they will ice up. Splitboard skins don't have a tail clip so they have a tendency to ice up a bit on the tail...
In deep powder both my factory and do-it-yourself rides kill it. I don't notice much of a difference in the pow at all except for the fact that your splitboard will weigh a lot more than your regular ride. And, with the factory metal base plates your feet are about a half inch higher than they are with a regular board. They make split specific bindings that eliminate that... but, I have not had the coin to buy them yet. They are on my list and come highly recommended.
I can actually make tele turns on the thing on low angle pow... but, it is not very easy to ski on hard pack. But... it's easy enough to get around on...
I use my split board all the time on hut trips and it does just fine… I love the thing and if I didn’t live right by a resort it is all I would ride because you can almost always find pow if you are willing to walk a little.