Both overhead squats and lunges are interesting exercise that require balance and control. I like overhead squats (I've got a kid doing them right now, in fact) for Oly lifters, and we use them in CF workouts quite a bit. They are not heavy enough to be considered a lower-body strength movement for anybody, but rather they are used as "core" work and upper-body support strength work for lots of different sports. Lunges, on the other hand, are usually done with light weights, and even done correctly so that they are not hard on the knees are still ineffective as a strength exercise because they are unilateral. Would you rather get your squat up to 405 or your lunge up to 135, and which would make you stronger? Hell, reading the questions on this board makes me tired, but I don't get to write it down in my journal. Lunges make you sore, I know, but that is not a criterion for an effective exercise.