I had a stent in place after an emergency infection/obstruction and it really wasn't that bad. However, every person is different & I would think every stent placement is different. Mine was internal w/o strings. With anti spasmodic drugs I was okay for the 10 days and lucky after my surgery to remove the stone I didn't have to have another stent.
I have a stent in place (without my knowledge or consent) and I'm sorry but its almost as worse as the stone itself. Get ready for constant urination (about 30x on average a day for me), blood and blood clots during urination, pain in the penis when you try to urinate, pain in the flank area(pressure building behind the kidney). You may not be able to hold your bladder for long, 2 hours max in my case. I am having it removed on Tuesday April 16th/2013. You may not be able to deal with the pain associated with the stent as I have to take morphine and percs just to get by. If you have the option, DON'T... take an alternative if its available. For the last month since its been in, I have barely left my home, driving is very uncomfortable and a 5 minute walk is not possible in my case. I hope these answers help, feel free to PM me for other details/questions.