I've also got a seton- just had it tightened yesterday for the second time, I've posted on here a few times, not too many people have had these it seems, or they're not posting a lot!
My surgeon wasn't sure what he was going to do with the seton in the beginning, I had a large incision on one side that was left open, and the seton which loops around the muscle from the right side of my rectum. It didn't really bother me at first, the incision was what bothered me, it looked horrible and hurt. Once the incision healed up (and I actually may still have a small fistula at the far end of the incision) he started tightening the seton, so I guess at that point it became a cutting seton. It is like a loop of rubber band. The first time he tightened it I was on here in lots of pain, this time either he didn't tighten as much or my body is not freaking out as badly. He said if the tightening bothered me too much, he could just go ahead and cut the muscle under anesthesia, but he said he usually has better success with the seton moving itself slowly outside of the body.
My seton actually seems to collect "stuff" sometimes, and once or twice felt like it was not draining properly, but a hot bath and some pressure usually seems to move whatever is in there out. I still never feel I can keep it clean enough, even with a handheld shower. He's tightening the seton b/c he says that it may be actually catching some poop and creating more of an infection than it should be, so I'm hoping once it finally works it's way out I'll be healed up... I still have a lot of drainage almost 2 months after the surgery, so I just use those little gauze pads. (I know TMI, but if I can't say it here where can I say it??) :)
I will say he did NOT warn me how much it would hurt the first time around. The nurse kind of chuckled and said it was like having your braces tightened, but I told her I had braces for years and this was a VERY different feeling...
Oh, and I was antibiotics for months before my surgery, but he said I could discontinue after the surgery, and I've felt so much better. That flagyl made me feel horrible and I lost weight, but now I'm starving all the time!