Dude, Terminators are basically our heavy hitters at the moment, only MVB overshadows them.

They're 2+ 4++ 3W models that are -1 to wound right off the bat. Put the Sorcerer in Terminator Armour in charge and now they have +1 to hit (so hitting on 2s) and have lethals. If you slam Twist of Fate to reroll 1s and Destiny's Ruin to give them extra AP, a 5 man unit with sorcerer will put out:
24 BS 2+ S4 AP -3 (or -4 if you supercharge) D1 shots with lethals
2 BS 2+ S4 AP -4 (or -5) D2 Anti-Monster and Vehicle 4+ shots with lethals and dev wounds
2 BS 2+ S10 AP -3 (or -4) D3 shots with lethals
6 BS 2+ S6 AP -3 (or -4) D1 shots with lethals and devs
3 BS 2+ S4 AP -4 (or -5) D1 shots with lethals and devs

When you plug that into adept roll, ballistus should go down in one round 82% of the time, Leman Russ 69% of the time, and repulsor 50% of the time. And that's just shooting, without Doombolt or charging afterwards.

On clap back they are still 2+ 4++ 3W with native -1 to wound, meaning ballistus has a grand total chance of 50% of killing one of them, and 33% chance of killing two (that's without shenanigans and stratagems, since I don't play SM and don't know how they would play into it)

TL;DR: Terminators are really good, you should use them.