x2. As stated before, as long as they're properly installed they should sound alright. My friend has 2 Type-R 10"s in his Contour and they sound pretty good. For the NiNe.1, I would think it would be alright but wiring multiple subs confuses me so I don't know for sure. SPL? Again, somewhere in the audible range. It depends on enclosure, power, vehicle, deadening, ect. ect.
if I was going to get type r's I would make sure they were the 05 models. They have made some changes. I like them and they will sound fine off that amp.