McMurrough is a huge threat and with his high ARM and his Total Immunity he is surprisingly survivable as well. The problem is that his weapons (grenades, smoke grenades, CC are all burst 1) are low burst which makes it hard to contest if the opponent has the advantage in positioning and you can't quite get into melee or use smoke to start a cage match. Simply chasing someone with his Chain Rifles will provoke dodge after dodge in order to sap orders and force you to pursue the enemy as they fail Guts rolls and dodge around buildings and into total cover.
Sometimes McMurrough needs to kill something and die doing it and it's the correct choice. So how?
Play chicken. Run McMurrough into base contact with a model. If they dodge, use CC due to its high chance of landing through the dodge-- that's simple thanks to the +3/-3 from Martial Arts 3. However, most players won't dodge due to a slightly higher die chance that almost every model has-- a pistol! Most models have a PH slightly higher than their BS, but not 3 higher. Being able to shoot their pistol, contest McMurrough's CC -and- if they get lucky they can put a wound on him will trick many players into shooting him. When they do, declare your order as firing your twin chain rifles just before you enter melee. The likelihood of McMurrough making his ARM roll against DAM 12 is much higher than your opponent making 2 ARM rolls against DAM 13.
You can also use this trick against a pair of units who are both within template range. Running McMurrough into base contact with one of them will likely prompt the other to shoot, and the one being aggressed upon to dodge-- and you place the twin templates on the model shooting. If both dodge, fantastic! Throw a smoke grenade in the path of the closest model's dodge so he can't escape it and CC them at your leisure. If both shoot, contest the shot with CC and MA3 in order to try to only take one Wound and not go unconscious-- not before you close the gap on the second model.
The caveat here is that if DAM 13 is not a threat against your opponent (ARM 4 or above I would always CC over dropping twin templates), or if McMurrough is not trading up in points cost (his 31 points against a 40+ model), or if McMurrough is not removing something dangerous to your faction (a model with ODD, a template and a high burst weapon). If McMurrough's survival is paramount, you should just be CCing in almost all cases, especially against TAGs, where McMurrough's Total Immunity will shine against the myriad effects TAG's CCWs have.