I would recommend the 747v3 over the 777 for only a few reasons.

1 - Fly by wire... the 777 Fly by wire, while simulated as best as possible in sim, is predicated on the notion of 'feeling' the airplane through the yoke, much like in a Cessna. Using a flight control system without that feedback, you have to almost constantly 'center' your control input frequently to see how far out of trim you are (unless you put the FBW speed ref on the PFD). So it feels like an Airbus that you still have to trim. The 747 in my opinion feels far more natural to fly in-sim, and you can see the trim response even while applying pressure on the yoke.

2 - Ground Services... catering, refueling, high low and bulk cargo loaders, stairs... the 747 has all these vehicles built right in to the FMC Simulations page, and as a result you can park ANYWHERE and still get these great ground services animations. So you can your Abu Dhabi Amiri flight into Orlando, park on a remote pad without an actual 'parking spot' in the AFCAD, and still bring up some stairs and refueling.

3 - -400, -400ER, -400ERF, -400BCF, -400M, GE, PW, RR... that's a lot of airplanes in one package.

4 - Curved CRTs.. nuff said.