I finally bottled/kegged the batch.
My thoughts:
First, it didn't save much, if any time by using 1 mini-keg and bottling the rest, if I had a second keg I think it would be a lot better.
To prime, I added 39g of dme to about a cup of water and boiled for a few minutes. I added it to the minikeg and then racked straight from the fermenter. Next time, I will probably add the dme straight to the minikeg without boiling. If carb tabs work in bottles why not dme without boiling? This will save a lot of time because I can start boiling the priming sugar for the bottles while racking to the keg.
There were no real problems and it was very easy. The only problem I saw with the keg is that it is hard to get all of the water out of the keg after sanitizing because the shape is a little odd.
I will leave some comments after tapping. Hopefully it is not over carbonated.