Don't have much to say about this build... It's viable, it can be fun if you like to use both missiles and lasers, because there's equal amount of both. Primarily for killing lights and support in fights against bigger Mechs. More firepower than using just SSRMs and less ammo dependent for those long matches. Bit on a hot side. Dunno, tell me how you liked it if you try it. I liked it.
Just bear in mind the COM-3A can do exactly the same thing but also has more flexible missile hardpoints that can do more. If you're not going to strip the left arm armor, it would be the superior choice.