Hyper-V And Hardware RAID.
No organization would install Hyper-v for test / lab , and would certainly opt for production. When setting up in Enterprise / SME environments, you would group the dissimilar arrays of drives / similar array of drives and form RAID.
Interestingly Hardware RAID and Hyper-v can co-exists , I have seen customers posting these questions in forum regarding usage of hardware RAID and co-existence with Hyper-v . Some customers were not able to install and some customers were able to.
Whether administrators should go with software RAID or Hardware RAID depends on their requirements, for Enterprise I would prefer hardware RAID.