Okay let me say first that I sparr with mma- & bjj-guys, thaiboxers and boxers. In addition to that I'm also into internal martial arts...I know alot of you might think this is for old farts, but I can tell you the applications of taiji and so on can be realy somthing else.
Sparring in a Gi with Bjj, Sambo, Bujinkan, and Judo practioners can be a bit boring when there is not much going on for a long time because of the holding on to the Gi. In a real- or MMA- fight they would not be able to do a lot of there stuff because of punches and so on. The croud is more divers with a lot of students, white- collar-job guys etc.
No Gi Sparring with MMA- & JKD- guys and wrestlers is more fun because it's more dynamic. There you have more bouncers, bodyguards and so on. It's true that a lot of young guys atrected to the sport are bodybuilding posers. Most of them don't stay for long. Or if they do, they try to skip learning good techniques by buying more strenght, what just makes them more clumbsy. But No- Gi grappling with real good guys can be like flowting. Considering Strikes? Well, with mma-gloves you just can't work as if you had boxing gloves on. And when you look at Fedor...He is just precise from all angles. Hands down!
Muay Thai is fun and Muay Boran is very intresting. But it's true most of the guys can't punch. The reson is simple they don't have a good stance, because they have to watch out for the kicks. If your front leg is to flat on the floor you eat hard lowkicks and that ain't fun. The croud is tough! Ther are thugs, pimps, bouncers, policeman, military etc.
What is my opinion on boxing? It's just a sweat science! The boxing workout is one of the best ( with wrestling in my opinion)! Before I started boxing with some good former amateurs and boxers from the national team, I would not have thought that it's so deep and divers. With some modifications it can be a very nice self defence art. I must admit, I'm not one of the guys who likes to fight on the ground in the street. But I think you should be a round fighter and know the game.
MMA and Boxing come from the same root Pankration. All of you boxing historiens also know that before James J. Corbett boxing wasn't to scientific and before the first rules were maid it was more like brawling or unscientific mma.;)
Coming back to the internal arts...well I know a group which also fights on the hard floor (no matts). They are very scientific, too! It's just like nothing I have seen before. Some of them look like whimps, but it's a bad mistake to underestimate them as fighters. The traping range is their game and you feel so helpless. The badest thing about it is they even don't use force.
There where I'm from most of the high level martial artists know each other.
One love, brothers!:D