I'm using a pixel3a with postmarketOS (now Nura) and sxmo as my daily driver (but I hardly ever call).
Calling and SMS works but there is indeed no echo cancellation so people complain they hear themselves if the volume is not low. I have a more reliable calling experience on the pixel3a than I had on the more powerful oneplus 6 where call audio was often broken.
Web browsing and podcasts should be no problem. The battery also holds well and suspend works. Wifi and mobile data work fine.