According to Wikipedia, this was Minolta's top of their mid-tier XG series, where it replaced the XG-9. It also claims this is the first camera with the new Minolta logo. It also appears to be the basis for their next top-line, manual focus SLR, the X-700.
$6 from the thrift shop and works fine.
The great thing about this camera is that it takes modern LR44 batteries, which can still be found without too much trouble.
Modern Photography Test: September 1981
Owner's Manual: Orphan Cameras.com
Reference: Wikipedia entry