If you haven't changed your tranny oil after 30000miles yet, you probably should.
I've tried two brands of synthetic tranny oil:
- Redline MT90
http://www.redlineoil.com/
- Motul Gear 300
http://www.motul.com/home.html
The first time I switched, I used Redline. I jumped to Motul when I had my clutch replaced. I'm currently using Redline again (only cuz it was on sale

). In the future, I'm sticking w/ Motul. The tranny, shifting and gear engagement just feels so much smoother w/ the Motul. What I normally do is buy the oil elsewhere and get the dealer to do it.
As for the cabin air filter (AC filter), just DIY. They charge more than oil change for that. Not worth it. Just buy the filter, open up the glove box, get behind in there and change it out yourself.