I've used the cheap VPS plans from OVH, Hetzner, and the 'baremetal ARM' instance from Scaleway (c1). This is not exactly an apples to apples comparison and all very anecdotal but:
OVH would typically have one extended outage a year, usually related to something like an excavator severing fibre cables or diesel generators not starting in a brownout. The supporting infrastructure was nice, you could get e.g. free primary DNS hosting for external domains, and the domains they sold were cheap too. RESTful API was nice. SSD performance & storage space (bumped up only recently) was on the low side. Quite a few datacenter locations to pick from.
Scaleway 'baremetal ARM' was a mixed bag. I didn't like the ipv4 NAT and related networking, they took a long time before you could use your own kernel (a feature promised at launch), crypto acceleration module on their Marvell ARM processors (CESA) didn't work for a long time due to a borked devicetree and after it did support was vestigial (had to patch and maintain your own libraries etc). Networked SSDs were a bit of a pain and a kernel update once broke them leaving all my instances on recovery console unable to mount anything... Performance was meh. It was the cheapest way to have a dedicated instance though.
I've been now on Hetzner for about two years and I don't have any particular complaints. It's solid. There was one bigger outage last year but didn't affect my datacenter. Pricing is very competitive, API is functional, processor crypto extensions (AES-NI) are exposed through the KVM (I think this wasn't the case with OVH but perhaps changed now). Only two datacenter locations (DE and FI). Cheap snapshots and backups. I barely ever need to log into the management console. HTH.
I've used OVH for several years (a few small Cloud VPSes). Never had any outages, but their web interface is very complex and unintuitive. I left because they messed up billing, then immediately threatened to delete my servers within hours of their mistaken billing (my creditcard was charged but their systems somehow didn't register it), then was charged a second time. They refused to acknowledge the error (even with screenshots, I had to do a chargeback instead). And their support took 2-3 days to respond to tickets.
I'm now a happy Hetzner customer since half a year. Support was quick, interface is simpler, and their small VPSes are even a bit more attractive.
