We actually did an analysis of various CC units in our codex, and the Lhamean was the suprise winner. They will die if you so much as look their way, but if you get into combat, they will do a lot of damage (for their points).
As others have said, 75 pts for a Venom with dual SC and a single Lhamean is amazing at lower point games. Throw 10 in a Raider and they will do damage (so long as they are supported by other elements, and dont need to survive overwatch)