I don't do barrels, but use the boots for reining. I have issues with sand accumulating in my SMB's. I recently switched over to the new Pegasus boots-LOVE them. So much easier to put on and off....and NO sand! XT new Product intro
I use the Elites and have no problem at all other than the sand getting in there. Im a penner...so after every run I just take them off and run my hands down my geldings legs to get rid of the dirt but the boots themselves are awesome..
Which sport boots are "best" is totally subjective and based on personal opinion/preferance, as you can see by the variety of answers you have already gotten.
As for myself, I have used the SMB combo boots, the SMB II boots, and the new SMB 3 boots.
And I love the SMB 3 boots! They fit really well and I have found they let minimal dirt/sand into the boot, compared to the other SMB boots I have tried.
I probably will never buy combo boots again only because the bell boots wear out faster than the actual boot does. But then again, they are nice because the bell boot never turns because it is attached.
Just know that whatever boot you do decide to go with, DO spend some nice $$$ on them. Yes, they will be expensive but if you take care of the boots they will last you a very long time. I've had the SMB II boots for about 7 years and they are still in great working condition, but I take really good care of my stuff.