Since they have come back in stock, I bought a Pi 4 2GB and a Pi 4 4GB. the 2GB model had 2 bent GPIO pins and rattled when shaken, so I opened an RMA request for it. the 4GB model has arrived, and it has small solder blobs on the back of the board (see images)

Is this normal or have I just got unlucky with both Pis? I managed to scrape off solder on the first image but they have left a mark on the board.
The 2GB model seems to be completely working and the 4GB one boots to the bootloader but I'm out of SD cards to test it any further. Should I also RMA the 4GB model or am I being silly here?
Thanks.