Hermi's are a very strange things. They come in different levels, being a little bit to extreme. They can come at different times of the flower stage. So hermi's are genetic and some are from stress.
Are hermi's good? Depends on how much of the plants has gone hermi. There are a lot of factors. I have worked with hermi's a little bit. Have grown seeds out from 4 generations of hermis. I have taken clones from hermi's. So there isn't that much info out there because most ppl pluck them and toss them to find out what happens. IMO all MJ well at lease 99% of MJ can be hermied ,or is able to go hermi, depending how its treated.
If my penis is 12" long. Is it a Foot?