[Time to change timing belt, wondering what else to change.]

I have a 2007 Legacy 2.5L that is due for a timing belt change, I have never had a Subie before,and the set-up of these engines is new to me. 

I'm not doing the work myself,. I'm thinking of taking it to the Subaru dealer to have it done, since so many people say to use OEM parts. I guess their 

is a benefit to doing this, 

I was wondering, when changing the belt, aside from the water pump, and I heard the tensioner is a good idea, what else would be good preventive measures

for this vehicle. I just need some good advice because it's quite a bit of money, and I want to do what's best for longevity, I hope to get this car to 200,000 miles, 

I hope that is realistic. Thanks. 

[93 Legacy Wagon L FWD]

Aside from the window, how did you get your car to go 305,000 miles? I've been asking around trying to figure out what I should have done when doing my timing belt for the first time. I know water pump, and maybe tensioner, but not sure what else would be good measure, Any ideas. I have an 97 Legacy.

[A few notes from experience on subaru]

Thanks, very good advice, and good timing for me, I was wondering if OEM parts were absolutely necessary for Subie's and I'm finding more and more people saying just what you said, Ok, I'm convinced now. 

I'm going to post, if I can figure out how to do it. on what parts should be replaced when doing a timing belt. I know the water pump should be changed, but what else, I hear the tensioner is a good idea. Any Ideas. Thanks.