Back then, it wasn't unheard of for a battery of Manticores to destroy the bulk of an enemy's forces in the first or second turn. In previous editions, Storm Eagle rockets had a much, much greater capacity to obliterate a large number of closely packed targets.
If it can fire all four rockets off, the the Manticore will routinely earn its points back. Unsurprisingly, the Manticore is a strong all purpose attacker causing ladles of grief to anything. The only downside is its limited ammunition, and perhaps less than stellar AP. A single manticore is a genuine threat to a huge number of targets, and remarkably doesn't break the bank at 145 points base (as of 9th edition). Like the Wyvern and Basilisk, it benefits not only from indirect fire, but also from the master of ordnance's reroll failed 1 to hit boost. The Manticore's Storm Eagle rocket is a thing of delight at 2d6 S10 AP -2 causing d3 wounds each. 2 CREEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEED!!!.