while I dont believe you will go to a chiro and get a stroke, here is my experience earlier this year:
I had a tendency to sleep on my stomach, and once in a while, I would wake up with severe neck pain. It was so bad one time, I had trouble moving my neck for about 10 days without severe pain, could not even get to work. So I checked out a chiro this year after a recommendation from brother in law that has had bad back and neck pain for years. He said when he went on a regular basis, he felt better than usual. So I went to the chiro he recommended. He took xrays and did some examining, and said my neck was in bad shape, but I was at the stage where "he could still help me and bring back the natural curve of my neck in time." There was no magic selling or hocus pocus, and I took him to be very upfront and honest. The plan was for me to come in 3 times a week for adjustments (@ $30 copay), for an undefined period of time, but hinted about 6 months to a year at least. On a side note, I have since heard from friends that their chiros have asked them to commit for at least a year (like a gym membership) to come for regular visits, but thats another story.
So, I starting going I felt better after the first visit, in which he adjusted my neck, and popped my back. Second visit was different, and we both knew it. He did something and my jaw went numb about 10 minutes after I left his office, and lasted for about 20 minutes (not kidding). I told him and he said he would do something a little less intense, and he stayed true. He adjusted me again and popped my back a few days later, and continue like this for weeks, and he would check alignment, etc one in while, and no more numbness. We talked about my neck and back, stretches I could, what I can expect, etc etc. All the while I am going, I never really felt that much better better, but I continued to go with an expectation that in time I would feel much better and these small adjustments were necessary, so I stuck with it.
Then the numbness came again. My LAST 3 visits were exactly like the 2nd visit; after the adjustments, my jaw went numb again. I called him after each visit to left him know. On the 3rd the last visit, I knew something was wrong because I would feel he put too much pressure or something, and it was a noticeably different sound than my other visits. Same thing happened on the 2nd to last visit, called him again to let him know, and the same on the last visit. That was it for me with the chiro. I had a talk with him face to face, not yelling and saying he sucked or anything, but told him what I felt and how I did not feel this was safe anymore, and would not be coming back. He was upset to hear this (like me saying he did not do his job well) but insisted if I did not want to go to him anymore, that he would recommend another chiro because he thought my neck was in bad shape and could still be corrected. After all, he went to a chiro as well and would try to find something that used a different technique. After going to him for about 4 months, I thought it would be best not to.
In all honesty, I gave this a shot, but got really scared when the numbness set in after the last 3 adjustments, and he could not say why, or do things differently. In all honesty, I really wanted to do this to improve the way I felt and gave it a shot, put forth the time and money as well, but it was not beneficial at all to me. I will say however that after a few weeks of stopping my visits my neck and back felt significantly better, better than I ever felt when I getting adjusted.
On the flipside, others I know say they have had great success with chiros. I asked my friends friend, a chiro of 8 years if/why he truly believes in what he does (btw, I never had him try to adjust me because this of my previous experience) and he said he went to one since he was young, and his mother went to one when she had very bad neck pain as well. He also said he has helped some people avoid surgery but giving them adjustments. I had no reason to doubt him, but after my experience i did not want to give it a second try. As mentioned before, this kind of care is alternative medicine. I really went into this with an open mind, did everything that was asked and then some, did my own research, but it did not work out for me, so ymmv.
On a side note, I made some changes which have helped my neck and back pain go away for the most part:
I dont sleep on my stomach (very hard because I did this for so many years)
I use a mckenzie cervical neck roll under my neck when I sleep (it helps so much)
I dont slouch when I walk or sit, but instead suck in the gut and stand tall
I stretch my neck and back
Also I have recently bought a neck pump and inversion table, and can hopefully benefit from them.