I would say that the biggest difference between a well-made pair of MMA shorts and surf trunks is in the stitching, the flex panels and the closure system.
As the poster above stated, the antibacterial coating is basically marketing BS, as such treatments are generally rated to last anywhere from 5-10 washes at best.
I think surf trunks will work just fine for someone who is taking a cardio kickboxing class, particularly if the shorts incorporate stretch fabric. However, I believe that a well-made pair of MMA shorts are a wise investment if you are going to be grappling regularly. The stitching is much more robust (triple stitching is key), and the expansion panels provide freedom of movement while decreasing the strain on critical seams. That being said, a cheaply made pair of MMA shorts are just as likely to blow out as surf trunks.
As was also mentioned above, you want to avoid metal snaps or buttons that are typically found on surf trunks--even external drawstrings can be problematic. When Dan acquired the Clinch Gear brand and brought me in to manage it, I was extremely bummed that the founder had not patented the forward folding closure system that we use on all our shorts.
Victor Corey invented that closure system in 2003, and it has since been utilized--legally--by many MMA brands (Warrior, Jaco, Death Clutch & more) and lately in the surfing industry. The reason is that it provides an extremely secure closure mechanism that is free of chafing. Unfortunately, Victor didn't have the cash to complete the patent process. He was a visionary though.
In addition to the waistband, he was the first to add expansion panels to sides and crotch. Again, financial resources prevented Victor from taking Clinch Gear to the next level, which is a shame, because he designed an awesome template for MMA shorts with features (or variations of them) that have since become commonplace. For example, Victor debuted Clinch Gear with the round expansion panel in the crotch about six months before Sprawl released their own version of that feature. Anyhow, while Dan and I upgraded the stitching, fit and fabric quality, Victor is the real innovator of the Clinch Gear brand.
FYI, I think Sprawl is also an innovative brand that helped shape the MMA shorts industry as we know it today, so please do not take any negative connotations from the statement above--just pointing out an interesting historical note. After all, Sprawl is the first MMA-specific loose fit board short that I can recall.
In surfing, the forward folding closure system prevents the discomfort that arises when a button, clasp or knotted drawstring rests between your waist and the surfboard when paddling. We've heard from many surfers over the years who have switched to Clinch Gear shorts. It's interesting, because the surfing industry clearly innovated the board shorts category, but MMA has definitely produced many technical innovations. We borrowed from them, and now they are borrowing from us. Go figure.
Sorry for the novel--it's just that I'm passionate about MMA shorts.
Aaron Crecy
Clinch Gear
