I haven't had any issues with mine (OLED model) FWIW. If you have an OLED model I think there is a way to put the card in the PSVSD, which might be more reliable.
Also I just ftp and drop roms on the sd card too.
To get the mod working I had to compile the software for macOS 10.13 as some libusb function wasn’t working correctly and wouldn’t inject the payload to the vita. This was well out of my comfort zone.