Personally I'm not impressed with the quality of the lossy encoding, it's not enough of a improvement on JPEG to make it worthwhile, for lossless however it's the best format I know of right now, compresses MUCH better than PNG, and both compression and decompression is MUCH faster.

FLIF compresses better than webp, but it also compresses/decompresses more slowly, and the difference in size is quite small so overall for lossless compression, WebP is my choice.