I have the MS-8 as part of my new system after I removed the entire Factory Alpine system and speakers. In addition to the MS-8, i have an RF 3.sixty.3 running as well to handle additional processing power. I also installed a new headunit to grid rid of the 430 UConnect.
One of the reasons I choose the MS-8 was for the surround sound Logic 7 matrix decoding. IMO, the Logic 7 is much better than the Alpine's Eurphony, including if it is used in a configuration other than surround sound. In the SRT and Summit GC, now you get the Logic 7 as part of the HK system. Many of the fine European HK system have also the the Logic 7 built-in.
The bottom line depends on the configuration you choose. For example, since you have to 2 JL 10's sitting around, you might want to have them hooked in a stereo configuration. This will leave you with 6 out of the 8 channels free. You might opt for a 3 way front with no center or rear. Then, I would suggested something other than the MS-8 because you need the ability to get into more detail tuning methods. This is one of the reasons why I have the RF.
Best for now and happy holidays.
Laredo X, Trail Rated, QTii, Sele-Terrian, Quadra Lift, Off-Road Adventure Package ii, Nokian Rotiva AT, Tow, AFE CAI, Custom Sound System ( HAT speakers, JLAudio , Pioneer , JBL MS-8 & RF 3.sixty.3 -- see the writeup link below for more details)