I bought a new 597 about a year ago and HATED it, cleaned it, coddled it, carefully set the guide rods, lots of issues. FTE mainly, but also FTL, last round hold open. So After trying unsuccessfully to sell it, started NOT cleaning it or anything, just shot it. Now it seems fine, its a fun gun. I had several hundred rounds through it at least before it started behaving. Last round hold open still doesn't work, but I think the little spring has sprang. This is a shame, cause the mag doesn't lock in with authority with the bolt closed. Its now a regularly used rifle. I also have a 30 round banana clip, and it seems to work fine, although others have reported issues. Mine was well under $300 scoped and delivered, with extra 30 rd mag. There is a dedicated 597 forum with tons of tricks and advice.
Good luck
T