I imagine the simple and most direct answer would be "Find out of yourself. What may or may not work for you, may or may not work for another."
However, that answer is too easy, a cop-out and a bit lame.
I can't exactly recall seeing it in a MMA event, still may have happened.
The one major reason for it's scarcity is that most people in MMA have never trained it at all, and those who have trained may not have trained it in a MMA context.
Just as with the double leg, which had to be altered and modified for MMA (you can shoot under punches, watch out for Guillotine, for example), the Russian also has to be modified for being struck while using it.
Tactically speaking, what technique has a force field when being applied? Name a technique that is so sound that you are not vulnerable in some fashion? When I jab, I am in danger of being countered w/ a cross, should I toss out jabbing?
When I double collar someone and am throwing knees, I am in danger of being hit with tight hooks and uppercuts. Double collars in the wastebasket?
On the surface the 2 on 1 appears to have a higher degree of vulnerability because there is one limb free to threaten you. However, for those who actually have the 2 on 1 at a high level and use it PROPERLY, constantly off-balancing, striking, positioning, looking for an immediate take-down, etc. there is a another paradigm.
For those who don't have a "Wrestlers" 2 on 1, it will take SERIOUS amounts of work to get it at a level to use in MMA, IMO. Hardly impossible, though.
We use the 2 on 1 in my gym. We do MMA as SPP for "Self-defense". We do not do Wrestling, BJJ, then some kickboxing and hope it gels together. It's MMA every day, all the time...strikes, wrestling, hooks, all available at any time in the drills and sparring. I have coached guys w/ no wrestling background, yet they use the 2 on 1 in a MMA environment. They have NEVER used a 2 on 1 in Wrestling!!!
Just like any technique, it has vulnerabilities which you need to shore up. You learn how to defend while using it, when to let it go and go to something else, how to counter when being struck, how to deal w/ being hit while using it, etc. Some of the takedowns are EASIER when someone is punching at you.
If you are CONSTANTLY applying pressure, keeping him off-balance, driving knees into anything, headbutts if allowed, postioning and re-positioning, looking to reach-around, looking for doubles, looking for carries, dragging & snapping, switching to other 2 on 1 variations, etc. you should be giving HIM a lot to worry about. He has to be concerned with being taken down, being hit, keeping his balance, and regaining a better postion and tie-up.
If someone is slapping it on and just hanging around in it, then I would suggest, they don't know what they are doing.
Obviously, how much prior experience you have had w/ the tie-up and more importantly how much experience you have had applying it in a striking environment will determine the degree of functionality of this for you.
Remember, it's not so much about the technique, but about the tactics, set-ups, timing, intent, etc. It's not the "new" technique that will revolutionize MMA, but another tool in your toolbox.
Train it and find out for yourself. You may find that it is a "Stupid, brainless, and dangerous technique to apply."
All the best,