The Red OOB T-55M

[Imp]

72 points. Game-wise, that's barely the cost of a Sabot round. Why, why why would anyone ever buy another tank?

For an easy game possibly, early 80s tanks from the main powers are probably around 300 - 350 points with higher experience. No need to buy the best one but some will be impenetrable from the front at least till very short range. They have far better fire control laser range finders giro etc probably better vision so if visibility is below 30 the T-55 is in trouble.
It was in huge trouble anyway unless the terrain allowed them to pop up 4 or 5 hexes away & swarm the opposition they would have been destroyed long before they became a real threat with comparative ease.