Well or bad? Because theres allot of agression in the family of my 3 males, the odds of them getting agressive are huge, and I'm not willing to risk that. This vet puts them to sleep with gas and has done many neuters before.
Both of my boys did really well. They don't give any pain medications besides a pre-op dose though, so you might want to get some infant ibuprofen before they go for their neuters so that you're prepared. I also started mine on some antibiotics before the procedure and continued after to complete the course. Probably not necessary, but that's the way we do things with surgeries in the lab, so I figured it couldn't hurt. If they use something like surgical glue to close the incisions, keep a good eye on them for the first 24 hours because they can sometimes pop open. One of my boys had this happen and I just glued it back closed and he healed up nicely. I'm kind of a DIY kind of person lol but you should discuss pain, infection and sutures with your vet just to make sure you're going in well informed and prepared.
My first experience was good and had a brilliants outcome, the second experiences wasn't quite so good but luckily still had a good outcome.
So the first time I had a pretty aggressive male rat, Tyrion, who didn't much like other rats or people at all! We took him in for his neuter and it was like a different rat came out the other end! He became my heart rat, he'd literally choose to be asleep in my arms over anything else! He moved in with two girlfriends and they got on very happily and for a short while he also lived with an elderly male rat and they got on great too! After his surgery he was given an injection of pain medication, the incision had been sewn up very nearly, everything was clean down there and it healed up really fast. So overall it was a great experience.
My second experience was a little more recent, this time with Casper who wasn't aggressive but we got him neutered so he could live with my girls (i wasn't planning on getting any more males but he was already an adult and living in the tiniest cage in pets at home so he ended up joining the family). We didn't get a call to say things had gone alright until way after the time we were told to expect it and when i picked him up i noticed his incision was very messy, there was lots of dried blood and i couldn't really make out what was what. He also seemed a little more tender down there than Tyrion had. He'd also been given an injection for the pain post op. He healed up but it took a little longer and thing look a little uneven down there but it's not something he's worried about. His personality didn't change at all and he now lives with four female rats and they get quite well (with an exception of Thea who can be a bit mean to him at times).
So overall, it is something to think about. There can be complications but generally it's a pretty simple procedure. I think my first experience may have led me to not think into the second neuter as much as i should have but everything turned out good in the end.
I've had 3 boys neutered, and all of them have done really great. Didn't bother the incision at all. I'd definitely get them pain killers. I've read that neuters can be more painful than spays. At least for the first couple days of healing. But my 3 boys all did great after surgery, I'm really glad I had it done. I hope your boys do well too and it helps with their issues!
There are a few posts in the Over the Rainbow Bridge section about neutering gone wrong, most have to do with incompetent vets... But that's where I would go to read about what happens when things go wrong and how they go wrong.
I got my boy from a similar situation as Jess. Single male rat, alone in a small cage. He was a sweetheart from the beginning, no aggression issues, but he was going to live with my females so I got him neutered. I went to a very competent vet who had done lots of neuters on small animals. He was done before the anticipated time and they did give me a dose of pain meds to take home. Everything was clean and he healed up great. I had read horror stories of abscesses after so I was a bit worried but its been months and he's totally fine.
I think you just have to pick the right vet. It seems like when people lose rats to neuters the vet kept them under too long.
I've had three boys neutered so far (two I didn't keep long after their neuter as I was really only fostering them), but they all went well. Pooka was neutered by a rather expensive vet and had some complications after such as bleeding because he wasn't stitched up well (there was an exposed string he pulled at) plus an abscess developed. The other two, Franklin and Picard, were neutered by a vet that charges $77... and they had no issues. That vet was amazing (though the office could be annoying).
There of course is always a risk when putting a rat under, as with any time any creature goes under as well as under the knife. So far, though, I have to say neutering has been worth the risk to me. Having had several bad experiences with hormonally aggressive males, I'm never having an intact male again.