I have a 2007 Civic Si sedan. I intended to get an EX with a 5-speed manual, but the Si was just too nice a car to drive. I can confirm that the Civic Si needs premium fuel and lots of it around town. I love my Si, and I haven't had any problems with it, but if I was driving it all the time as a delivery vehicle, I'd be making a lot more money with something that gets 10 mpg better on regular fuel. Also, the Civic Si is pretty intense. If you're driving on crummy city streets, you might be more comfortable in a cushy EX, and you'll also save money when it comes time to replace the 16 tires instead of the Si's 17s. And when tire replacement time comes around, you can pick some high mileage specials what will last 80,000 miles, while the longest lasting tires for the Si might be good for 45,000 miles. Mind you, I'd be better off financially if I'd gotten an EX too, but I do enjoy every time I get behind the wheel of my Si.