While I applaud Meng for the stellar job they did on their recent A7V (it makes the old Tauro kit look like a toy), I'm very disappointed at the way they've handled the whole, "Now that you've bought the original kit, here's a Deluxe Edition you really must buy, because, well, it's got an engine". Seems like a sneaky cash-grab to me. I'm considering selling my original to make way for the Deluxe version. I was hoping they would sell the engine as a stand alone item but as far as I know that hasn't happened.
I'd really like to do a build featuring a removable side panel to show off the interior but that really can't be done without the engine.
Judging from the comments I've seen on various forums the "deluxe" edition (and I agree it seems a bit like a cash grab) is sold out virtually everywhere, so I'd hang on to your kit till you find the "deluxe" one.