The downside to most B-rated equipment is that they usually weigh the most. Sure, you get good results, but you pay the jump price. For me, range is more important than heat efficiency, especially on an explorer build. If you run a small A-rated PSU, just enough power to run everything, then heat qu...
The best hunter ship I've flown to date is the FAS. It's quicker than the Vulture and Python, turns almost as well as the Vulture, has better weapon placement than the Clipper, and can be made into a flying tank with over 2000 armour points. It has enough internals and hardpoints to be able to refit...