I agree on both, though I don't think either are really sleepers at this point, but rather that Jones is pretty much a full time WR3, and McD is a WR3 based on matchups. But I think you're spot on. The funny thing is it'd almost be more of a sleeper pick this weekend to go Lee Evans. Or Larry Fitzgerald.
Also, remember (I'm totally spamming about this... I realize) the Bears D is not just down Vash and Peanut. It's also probably missing Briggs, and almost 100% certainly missing Harris (I heard someone say he may try to play on it... can't imagine that, since the Bears are counting on him... one of the best in the NFL at his position.) Then remember that Brown is on IR. And flash back to Archuleta TRYING to cover against the pass. There is almost no way the Lions receivers have a bad day... unless Kitna goes out of his way to focus on one guy, or something wacky like that. But Roy is a MUST start, and McDonald is like a Kevin Curtis type of play, from his mini peak last year. Potential for lots of yards and maybe a score or two.