Thanks for your input, I've only tried Chroma a little bit so far and had a pretty good experience. What they also have going for them is a big community on discord that can be helpful.
Many of them are open source and you can host them yourself. That would make it more cost effective. Also someone mentioned https://turbopuffer.com/. That seems like a good alternative if you're looking for something economical.
I quickly took a look at the redisearch ANN Benchmarks and they seem to stack up against the others (more or less same level as Milvus) in the comparison when it comes to QPS and Latency.
Yeah, that's the difference we've seen according to the QPS for the ANN Benchmarks. The same story seems to be true for other datasets too. We're looking at a 0.9 recall.
The way you explain hybrid search aligns with my understanding. Pinecone has a good article about it here https://www.pinecone.io/learn/hybrid-search-intro/. From my understanding, all vector DBs support this.
(Disclaimer, Lukas and I are co-founders)