Currently I'm using OCZ Rally 2 16Gb for macOS installation. I was following Jake Lo's Clover Guide for Dell systems, which says to use USB flash drive with 16Gb minimum storage and this is exactly what I have used. I have other 8Gb sticks for testing Linux distributions, but I don't see how the storage of installation media might affect proper drive formatting and I suppose 8Gb will be too low for Mojave to use anyway.
It is strange that I have any problems at all since I'm using exact Clover folder as a guy from another 7490 thread. He had success with Mojave install with only touchpad and Intel networking missing. Maybe he might help me figure out what's wrong. Sadly I don't have enough knowledge to understand why two machines with same config can't both have successful Mojave installation. I triple checked BIOS settings and don't have spare SSD other than Micron. I would have likely used some Sasmung EVO instead.
Thank you for your time helping me anyway