I haven't tested it extensively but I found that when I used Claude Code with it, it was reasonably fast (but actual Claude was way faster), but when I tried to use the API itself manually, it would be super slow.
My guess would be think they're filtering the traffic and prioritizing certain types. On my own script, I ran into a rate limit after 7 requests!
Do they or any other providers offer any improvements on the often-chronicled variability of quality/effort from the major two services e.g. during peak hours?