Look. Just about anyone can create some "database" and declare it "rock-solid". Frankly, a simple key-value store is built in most languages.
Do you have more than that? Do you have benchmarks? You know, competing against the other providers?
I think the argument in favor of it being more reliable is an easier one, however, as Bedrock is specifically designed (and used, at scale, for 8 years) to provide highly available redundancy in the form of WAN-replication and automatic failover.
Regardless, I think you'll agree that "rock-solid" is not a precise technical term, and I hope you'll allow a bit of play on words. Whether or not it's literally as solid as a rock is unclear, but it is definitely very reliable -- and more reliable than most.