I had a look at how the T-REX modes score. First, in all T-REX modes, be aware that if there’s a green dinosaur shot on the playfield, the dino will sometimes pretend to be a mode shot even though it isn’t: If the dino shot is a mode shot at the same time, it will flash green/orange, which it should. If you then hit a DIFFERENT shot that by the mode rules should unlight that orange shot, it will still flash green/orange, which it shouldn’t.
Chase and Encounter end automatically after a certain number of shots, while Rampage doesn’t, so the time bonus of 1M/sec doesn’t apply to the latter.
Chase: Alternate orange shots and truck shots, with orange shots starting at 3M and increasing by 3M, and truck shots starting at 1M and increasing by 1M. Orange shots made within a few seconds of the last scoring truck shot pay double. The mode automatically ends after 5 orange shots have been made. Min value for a complete run is 55M, averaging about 6M/shot, unmultiplied max value without time bonus is 97M, averaging about 11M/shot.
Encounter: Truck starts the mode for 2M, then alternate any of the three shots on the right with the T-Rex ramp, where the T-Rex ramp is always 5M, and the first right shot is 4M base value, sencond 8M, third 10M. This base value is multiplied when collecting it on more difficult shots: heli ramp 1x, right ramp 2x, right orbit 3x. The mode automatically ends after three shots on the right have been collected. Min value for a complete run is 34M, averaging about 6M/shot, unmultiplied max value without time bonus is 78M, averaging 13M/shot.
Rampage: Shoot right or left ramp for 2M to qualify collect on left ramp. The first collect is 10M base value, then has to be qualified again and increases by 5M each time. Before collecting, you can shoot the heli ramp for 500K and a 2x on the next collect, or the tower ramp for 500K and a 3x. Those multipliers stack, so shooting both shots makes the next collect 6x, which can be huge. Unfortunately, the animation seems to have quite low priority, so pretty much any other animation like rescue, Pteranodon, combo, dino slowed, etc. will completely prevent the collect animation from playing (no sound either). This, combined with the fact that the left ramp is always lit in this mode, means that it can look like a huge collect didn’t register when in fact it did.
Rampage doesn’t end after some number of shots, so there’s no min/max value, and it also makes it the most interesting mode for risk/reward considerations. Let’s say you manage to get in 12 shots during the mode: Going for no multipliers makes 147M or about 12M/shot, always going for 2x makes 150M or about 12M/shot, always going for 3x makes 250M or about 21M/shot, always going for 6x makes 279M or about 23/shot. It might make sense to build up the base value with easy shots, leaving just enough time to go for a 6x (or even 12x with 2x playfield) collect in the end.
@raydaypinball, I think you mean Rampage, not Chase. That particular combo immediately after starting Rampage will give you about 115M, with the last left ramp shot being a 90M collect.