Mancini has (or had) a deal on the housing, pump, and neck for a very competitive price. AND they have a 10% discount going on, I think. So there is not that much difference in price between the two.

Personally, I have had mixed success with 440 Source. Half the stuff I have bought from them has been fine. And half has been junk that they would do nothing about. If fact, they didn't even want to hear about it.

I have never had any problem with anything from Mancini. But their stuff is usually more expensive.

Good luck with whatever you decide.