I decided to try Flashrom on one of the Lenovo systems we have onsite here. Reading appears to work and it verifies against the chip (although the resulting file does not match the size of file provided by Lenovo (Lenovo's file is larger) so I'm not sure if there's some extra stuff in there). Below is the message I receive when attempting to write to flash. I have attached the output from the standard tools. The BIOS chip on this board is socketed and I have other systems of the same type so I can easily swap chips if something goes south. If there's anything else I can do/test I'd be more than happy to try!
flashrom v0.9.0-runknown No coreboot table found. Found chipset "NVIDIA MCP51", enabling flash write... OK. This chipset supports the following protocols: Non-SPI. Calibrating delay loop... OK. Found chip "SST SST49LF040B" (512 KB, LPC) at physical address 0xfff80000. Flash image seems to be a legacy BIOS. Disabling checks. Writing flash chip... ERASE FAILED at 0x00000000! Expected=0xff, Read=0x4e, failed byte count from 0x00000000-0x0000ffff: 0xf0b1 ERASE FAILED! ERASE FAILED! ERASE FAILED! ERASE FAILED! FAILED!