Neither. Use Coypu. It wraps Selenium. Much more durable. https://github.com/featurist/coypu
Update
Ye Oliver you're right. Ok why's it better?
Personally I've found the Selenium driver for IE in particular to be very fragile - there's a number of 'standard' driver exceptions that I've time again found when driving Selenium for Unit Tests on ajax heavy websites.
Did I mention I want to write my scripts in c# as a Test Project ? Yes Acceptance Tests within a continous build deployment.
Well Coypu deals with the above. It's a wrapper for Selenium that allows test fixtures such as,
browser.Visit("file:///C:/users/adiel/localstuff.htm")
browser.Select("toyota").From("make");
browser.ClickButton("Search");
... which will spin up a (configurable brand of) browser and run the script. It works great with scoped regions and is VERY extendable.
There's more examples at GitHub and as Olvier below mentions, Adrian's video is excellent. I think it's the best way to drive browser based tests in the .Net world and tries to follow it's Ruby namesake capybara
