My experiences with OVH's cloud platform has been a bit dated. I've been using their cloud platform since 2012, especially when their OpenVZ "Cloud" VMs were nested VMs inside their VMWare containers and had regular network outages (due to noisy neighbors) or restarting the VM every few hours. I switched to their VMWare VMs and they work like a charm. Granted some see it as a bit pricey for a small project but it's still cheaper than some other options.
My experience with OVH's KVM Openstack line was when it was still maturing as a RunAbove product. I remember they had problems out the gate and at one point had regular service restarts and I think at one point had a storage problem becoming read-only. I stopped using them since then and just chalked it up as another problem with using OVH's cheapest cloud platform. They've never worked out for me.
However, for those who stuck around and also bought KVMs from OVH after they "graduated" from RunAbove, I believe it works to an extent. It's not the best, it's obviously focused on minimizing costs and maximizing possible resources and reliability, and (this is my own speculation now) I think their server density is fairly high (VMs per host node). I haven't heard of any major problems lately with their KVM platform but again, I wouldn't put anything intensive on there either.
If cost is a major factor for you, then go with OVH's Openstack KVM line. If you still need fairly solid reliability, I think going with AWS or GCP might be worth another look. If you're fine with a VPS starting out without Ceph, NVMe, etc, then I'd really suggest you hit up Linode. Linode offers some of the best resources per cost ratio while still providing a decent reliability factor. If you really do need reliable storage then I'd look at DigitalOcean's Block-Storage (also known as network storage). Once you've grown your operation a bit more and have more resources and funds, then I think it'd be worth re-visiting the idea of moving to AWS or GCP or any other cloud platforms.
YMMV as I am just one person.
If you want a more detailed response feel free to let me know.
Best of luck!