I don't rec stuff because I only read people I know (who tend to have enough other reccers out there) or off of recs (which means that by the time I read it, reccing would be superfluous).

But I think people can understand "liked, but 'ware the publish date" and/or "not the best thing ever, but there's this one section..." sort of language. Although that second one is trickier and more likely to poke sensitive spots, despite your recs being entirely your opinion. Putting them in their own category and post, as someone up above suggested, sounds like a good idea. Mixing them in with stories without "warnings" would highlight the difference more than grouping them, I think.