Paid relays are not essentially better than non paid. Latency matters the most in lag free Nostr UX.
Relays should be curated as latency can vary by location.
Try a mix of popular public relays(ensure you get most notes) and paid relays (reduced spam - can be set to global only), but ensure the one's you connect to are < 100ms Latency for you on nostr.watch
Over 3g with 2 relays, iris snort, looks ok. (some missing events, but wip...)
Is there a max relay recommendation as a client?
Generally around 10 with any bad performing ones removed seems like a good number.
Will the client readd them if performance of one relay improves?
The client won’t. You might want to make a note of them to re-add them later. Are you using Damus?
What is the average cost to run a "good" relay?
Check out nostr.watch where you can check things like recent uptime, and latency #[3]
#[1]
