As for battle, I used this baby out with my friends in our first Apocalypse/PlanetStrike game (this was circa 2009?) and it was overpowered. I think we're going to have to limit aircraft to one per side (as in I'll lend my thunderbolt to the guy without one and the other player will ensure he brings his). It ended up one sided with air support (my side had 3 craft vs 0). It didn't REALLY matter though since we couldn't hold off their ground forces and they won on turn 6 however if I'd been an attacker I think my team would have won by turn 3. Really fun anyway.
The engines are definitely undersized compared to the stock model, but oddly I think they're actually the same length and width, however the FW model's are taller and go through the wing. I was at a complete loss on how to make engines that looked good and would fit the model, and all I could think of was the valkyrie ones. I've noticed that from top down they don't look too bad, but from straight on they're definitely a tad small. On the plus side since they'll be painted black they won't be drawing anyones attention