Despite my better judgement and the advice I received, I took the second list and did not play test it.
I was very impressed with the Incubi. The first game I played, they completely destroyed a Tactical squad. With their second pain token, they proceeded to charge a Night Spinner and ravaged it with their STR 5 AP 2 weapons. The 315 point deathstar (5 Incubi, Succubus, Haemoncus Raider) made its points back without breaking a sweat.
The second game, they assaulted a large scout squad in a forest and utterly crushed it before taking on a ten man tactical squad.
The last game, they failed in a game breaking way. They failed a 6" charge against a thirty man strong Fire Warrior gunline. I know you'll say that was ill advised but I actually managed to disable Tau overwatch by throwing the Haemonculus at it first. Through a bizarre target priority conundrum, the Succubus and a single Incubus managed to survive. The duo subsequently charged and ground their way through twenty Fire Warriors. The Tau line had been so compromised that Eldrad was forced to cast Death Mission on himself--to little avail.
Although the squad did not make it's points back, it was also responsible for three kill points. If it had not failed the initial charge, a squad of Wyches would have been able to eliminate a Hammerhead and Pathfinders. It is also likely that the squad would have moved on to kill several Dark Reapers and another squad of Fire Warriors because it would have been four men stronger. In other words, the problem had more to do with poor rolling at a critical point than anything else.