Here is a quick comparison for boating 4x ATM12s looking at trade offs between speed, cooling and ammo capacity. 90 tons 9 tons ammo 17 heat sinks 69.3 kph No Tag Big ears Note: MCII-4 can run tag, but has two extra slots taken up by arm actuators. 90 tons 10 tons ammo 15 heat sinks 58.5 kph Tag 3x Jump Jets 90 tons 8 tons 16 heat sinks 58.5 kph 4x MPL 90 tons 10 tons ammo 18 heat sinks 64.8 kph Tag ECM Tag pod is huge 85 tons 9 tons ammo 15 heat sinks 71.5 kph Light Tag Hero 75 tons 8 tons ammo 12 heat sinks 64.8 kph Tag 4 Jump Jets Hero Chassis Optional Under weight - could trade Tag for Medium Pulse Laser 70 tons 9 tons ammo 13 heat sinks 64.8 kph Tag 65 tons 4 tons 13 heat sinks 81.0 kph Low on armor Not viable 60 tons 7.5 tons ammo 10 heat sinks 68.9 kph Light Tag Honorable Mention 75 tons 9 tons ammo 70.2 kph 14 heat sinks Tag ONLY ATM 45
Boba Fat is a better all around build. Because of its secondary weaponry, I wasn't including it in the boat category. SNV only has a max 325 engine and speed really help positioning, which is very critical for ATMs. So unless you hate the Mad Cat II ears, you tend to get more for your money with a MCII-4. I'll add Boba Fat and a JJ version, since the Supernova does have a lot better armor density without the ears.
Winner is which one matches with your favorite pros and acceptable cons. Blood Asp has ECM and works well. If that is too slow for you try the Scorch. If you don’t have the hero try one of the others.
A word of warning, it is much better to have some short to medium range weapons. Your match score floor will be higher and less games that you get caught out by a light.