ill give you a breakdown on the pros and cons of the towers from TT and Scythe and the heatsinks from Thermalright.
1. Pros about towerheatsinks: They cool better than any other heatsink.
2. Cons: They dont blow down on the motherboard to cool RAM or MOSFETs.
3. Pros for the XP-120: It cools down the MOSFETs and sometimes the RAM.
4. Cons: Doesnt cool as well as the towers. Usually requires a high powered fan with lots of pressure. The XP-120 is discontinued and it is replaced by the SI-120 which isnt as good.
The pluses of the Scythe Ninja is that it really shines with a low CFM fan, so its good for quietness. The Scythe Ninja is the best out of those three, and if you are using a Antec P-180, the exhaust fans on the case are perfect for the Scythe Ninja.