Back in the 1980s and 1990s, I used rebuild Bosch alternator all the time, zero issues.
For the last 5-10 years, the quality of the rebuilt alternator has gone down a lot (do a google search and you will see). My theory is they use short-cut or using Chinese parts etc.
Just when you think you put a good rebuilt alternator in, it fails 6 months later.
Considering that the laternator is a crucial item (whn it fails, you are stranded), I take no chance.
This is why when you rebuild it yourself, you know for sure you put quality parts in there:
- Bearings x2
- Slip rings are optional.
- VR: stick to Bosch or HUCO and nothing else.