I had two boys from the same litter. The issue is that as they mature they can start fighting as their hormones kick in and so may need separating and re-introducing later. There is always the risk that they won't get on when they are reintroduced. Fortunately, my two boys seemed to get on well, but sadly one of them died whilst they were being neutered- it's rare for that to happen though. Hopefully someone else will have more experience for you.
Would you consider getting rabbits from a rescue? They often have young bunnies in through no fault of their own and will always take a rabbit back into their care if the worst should happen and a bond breaks down. They often have happily bonded pairs who have been neutered and vaccinated - having just paid £140 for a spay, trust me their adoption fees are amazing value for money!