Unlikely you are going to overwhelm Redis in a non-deterministic fashion. What do you even mean by overwhelm?
The post only concerns itself with in-memory workloads; I don't think Aerospike is competition in this space, while their advantage is against workloads working against SSD backed datasets. "After Google published a blog post “Cassandra Hits One Million Writes Per Second on Google Compute Engine” – using 300 nodes, we followed the same steps and documented how Aerospike Hits One Million Writes Per Second With Just 50 Nodes On Google Compute Engine. [...] Aerospike on SSD is very comparable to that of RAM. At 100% write, the SSDs are able to sustain 226,000 transactions per second compared to 239,000 for RAM." [0] Redis would have no problem hitting 250K IOPS on just a single core provided by GCE (or AWS EC2 or similar).
A single Redis instance uses a single CPU core so yeah, hitting the its limits (no matter how high) is always a possibility. OTOH, there's always the possibility for sharding and clustering a Redis database to scale it up 'n out, thus making "overwhelming" it less trivial.
