Oh, boy, I wish I chimed in sooner. I have both the 104HF and a 2xUL112 setup driven by an LMII. Granted, I have heard that the UL212 sound different than a 2x112 rig, but I would venture to say that they are similar in tone (but not in wattage).
I have to hand out some love to what Peter said. People listen to MB cabs at GC and tend to be somewhat lukewarm about them. They don't tend to "sparkle" like other "hi-fi" cabs do. And I can say first hand that when I am practicing solo, I really love the tone of my Epifani's. The Markbass cabs are a little more middy to me solo'ed, the tweets are not as bright and don't seem to have the same presence.
On the other hand, when I am competing against my hard-hitting drummer and that gosh-darn Marshall 410+212 stack, the 2xUL112 cannot cut the mustard like the 104HF. I think the voicing on the Markbass is made to cut through. It took me a while to realize why...
I think it has to do with the way you need to sit in a pocket in the mix. The tone that often works best in a live setting is a mid-biased somewhat "nasally" tone that can sound less pleasing when solo'ed. I am not a professional by any means, but when I mix on my Apple with Logic or GB, I find myself coming to the same conclusions. Also, a lot of the shimmery hi-fi that we are goo-goo over gets lost somewhere in the guitard bandwith. And that lowend that everyone likes to feel? It will compete with the kick drum. I have found if I scoop my tone, I will get lost.
Of course, this is one unprofessional humble opinion. I am debating whether or not to hit post since you have already ordered but perhaps this will help you EQ things if you need to when you get your rig

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I love both the rigs for different reasons. Can I carry the 410 with my pinky like I can one 112? Nope.
The below thread is not directly applicable because the 212 can handle more than the 2x112, but it's interesting reading:
Epifani Ul 112x2 not enough speaker