FYI--
The Sony MEX-B100BT is 100 watts PEAK POWER.. meaning 25w x 4 not 100w x 4 just want to clear that up for folks reading/watching.... which is equivalent to the output of the factory deck. The benefit to doing this is you're freed up from HD head unit needing a flash or line levelers and have a much cleaner sound capability with add-ons.
I don't want to sound negative or harsh... don't take it that way please.... but a little hindsight is in order....
Your subs should have been mounted on the INNER SIDE of the bags ( inboard ) for a cleaner look and be mounted internally for a bit more protection from the elements. Also, did you research the subs for the amount of airspace required to perform at their optimum? Are the subs designed for a 'free-air' environment, sealed or vented enclosure? When installing subs in an enclosure, the correct speaker for the enclosure ( sealed or vented ) is key to the performance and sound.
Most people don't have the 360+ days a year with sun and no rain as you do in SOCAL ( I lived in Irvine/Tustin for 7+ years and loved the weather) ....so those subs mounted like that would take a beating and not last long.... at least not here in Reno. I ride year round as long as there is no snow/ice on the roads... Single digit weather means an extra layer of clothes is all.. LOL!
The metra kit is a very good kit from everyone I have talked to that has it, the hand control module had some issues, but were resolved with a few updates to the firmware. I may be looking into this in the future to expand my sound a bit more freely from the HD unit.
It sounds good... you did a great job on the install... if you are happy, that's all that matters.