I should doing that, and more, shortly as part of my "Entry Level Bass Combo Shootout" for
Bass Gear Magazine. It's a bit of an undertaking, as I have nearly 20 different combos to get through, but the new X4C is one of them, as is the Boss Dual Cube Bass LX.
Also, FWIW, here is a
link to my original X4 review. I ended up buying the X4 after the review, and my son currently has it. He is out of state doing an 8-month coop for college, and he wanted to pick up electric guitar while he was out there, so he's using the X4 to stream music, play along on guitar, and listen to it all via headphones (so he doesn't upset the neighbors). What a versatile little amp!