It's great but you definitely pay for it. Encoding can be really slow, and to a lesser extent decoding as well.

So I still end up using .jpg quite often, or .webp as a good middle ground

You can adjust how much "effort" the avif encoder puts on images.

The default speed in libavif (-s 6 in avifenc) is fast enough, and it has been used by big CDNs to encode AVIFs for years. You can make the encoder as fast or slow as you'd like, depending on your compute/compression efficiency trade-off requirements.