BTF/PTM

Anyone else here notice that their 6M tranny is incredibly finicky? What I mean is, on certain days the thing shifts smooth as silk, and other days the thing will fight me thru every gear, feels like it's full of rocks or something. I've noticed that it does shift better when it's warmed up, which is to be expected, but it just seems like some days it just doesn't want to cooperate, almost like a teenager who just wants to stay in bed instead of going to school.

Also, has anyone noticed that the shift gate is kinda loose? Sometimes it feels like there's a lot of play in the shift pattern, like maybe the reason it doesn't shift smoothly is because the shifter isn't quite lined up where it should be.

I ask these questions becuz by now it should be well broken in, it's a 2006 with 7,900 miles. Should I change the tranny fluid? The Nissan dealership swears that it doesn't need new fluid till 30,000 miles and that I shouldn't need to mess with it. But, I feel like I should change it to flush out any metal particles that are in the oil from the break-in of all the parts, just like I did with the engine. What say you?