Yes, the F product is the same on all a/c. The A330 and A340 F cabins are actually identical.

Between the A330/A340 and the B747, the difference lies in the configuration. Both aircraft are 4-across, but on Airbus aircraft, these seats are in a 1-2-1 configuration, whereas on the Boeing it's 2-2.

If you're travelling alone, you may prefer the privacy of the single window seats on the Airbus. If travelling with a partner, the 747 configuration is fine, especially if one of you likes to have a window seat.

Beyond the product, I would also think about the ease of the connection - MUC wins in this regard. DUS is also an easy place to connect, but does not have the same level of ground facilities as you would see in MUC or FRA (no FCL/FCT, just a SEN lounge). FRA is a pain in the backside for connections.

Personally, my choice would be the A346 via MUC if travelling alone.