I appreciate your honest question, as many people are afraid to ask this one.
I think it is way too simple to say if you go to Mexico bad things will happen, where if you stay in the states all will be well.
I am going to use the analogy of my hair. I have very annoying, thick, and frizzy hair. My hair is complicated to cut and to style. I have been to Lotsofcuts R Us and I have been to a salon to have my hair done.
For this analogy, let’s say Lotsofcuts R Us is Mexico dentistry and a beauty salon corresponds to a private practice general dentist.
Truthfully, there have been times when Lotsofcuts R Us did a superb job. However, when I went to Lotsofcuts R Us on a regular basis, they were not consistent. I saw different stylists and their ability level differed. Sometimes there was not enough time for the stylist to deal with the amount of hair that I have. There were occasions when the stylist used a product with which he/she was obviously unfamiliar and my hair responded poorly.
It is also worth noting that when a stylist messed up my hair, it took months ( one time it took a year!) for my hair to grow out and look normal again.
(Remember that hair will grow back, but a tooth will not fix itself over a period of time.)
So, for me, I know that my hair is too complicated for Lotsofcuts R Us . My husband has hair that is about a millimeter long. Once a month he has a stylist take the clippers and cut all the hair he has off to about a half millimeter.
Lotsofcuts R Us works perfect for him. They are always consistent and the time alotted is always enough.
(There are people who have simple dental problems that are easy to fix. Mexico might work for them.)
When I go to the salon on regular basis, I get superb work. The stylsit is always the same and he is generally consistent. There is generally enough time for the stylist to deal with the amount of hair that I have. Most of the time, the stylist has handpicked his products and knows what will work on my hair.
However, there have been a couple times when the salon stylist messed up my hair. However, the problem was able to be corrected in a month or less.
Translating all this to dentistry: you can absolutely get quality care in Mexico and you can absolutely get a poor result at a private practice dentist in the states. But your odds of getting good care are much higher with the private practice USA dentist.