Mezzo Forte is an anime that feels like it's trying to cram a two hour story into a sixty minute OVA, and unfortunately this has a fundamentally negative effect on just about every aspect of the story. A lack of establishing exposition left me feeling lost as to who the characters are (both individually and as a group), what the time period of the setting is, etc. While you're able to somewhat piece it together by the end, the story ends up feeling wonky and poorly paced as a result. The characters are very shallow and predominantly feel like caricatures of classic action film tropes, and the overall plotline - barring a few admittedly surprising twists - is pretty formulaic.
The hentai element of the show is gratuitous and for the most part unnecessary, and its inclusion really felt like a studio mandate rather than something that was an originally intended part of the show. The sex scenes have some especially problematic subtext that could be very uncomfortable for some viewers. I don't feel I would have missed anything by watching the censored version of the OVA, which is a metric I usually use when recommending a censored/uncensored version of any show.
I will give it credit for some solid animation, really interesting and memorable fight scenes, and good character design. Overall, however, it was just okay. I won't watch it again and I wouldn't really recommend it. Watch it if you really enjoy formulaic "mercs vs. mobsters" stories or want a hentai with a decent story. Otherwise, I'd just look up a few of the fight scenes on YouTube, because they are admittedly pretty cool.
I've heard there's a film cut which blends the OVA episodes together with an extra twenty minutes of footage, and I'd be interested to see if this fixes any of the OVA's problems.