Instant oats make an excellent adjunct for some beer styles, but I don't think a beer using oats as the primary fermentable would taste very good. You'd still need to mash it with plenty of six-row barley to get it to convert. It just sounds like it would be bland, maybe a bit astringent and chalky.
The Fiesty(sic) Goat Brewery est. 2007 & Clusterfuggle Experimental Ales est. 2009
Planned: sLambic II, Flanders Red II, Orange Blossom Mead, Fat Man Porter
Primary:sLambic I, Janet's Brown
Secondary: Toasted Caramel Port, Flanders Red
Kegged: Hefeweizen, Centurion Falcon IPA< Dark Saison
2013 dump volume: ~2 gallons