In 2007 I had a peri-anal abscess, diagnosed by MRI and a procedure to open the fistula and insert a seton. It took a while to get used to, I use a dilator and it made that more uncomfortable so I had the first seton replaced, then the second one broke and I had a third inserted, which I still have.
Apart from the hospital visits it's not been much bother - I only notice it when I wash that area. I do sometimes get a little nightime incontinenece (I use pads) but I also had that before so I don't know if the seton contributes. In my case the Doc reckons it's best left petmanently as my fistula runs through my sphincter muscles and any surgical intervention there risks causing more serious bowel incontinence.
Overall I'd say my abscess was far worse and the seton is just another thing I got used to, not as bad to live with as I imagined before I had it.