Well i bought a Honda Civic LX coupe, same engine and everything as the EX, yours will just have 6 disc cd changer, alloy wheels, trunk release on the key, and some other minor upgrades over mine.
My opinion is that is a great car, it gets great gas mileage. In fact i've managed to get about 35mpg average on pretty much every tank i use. I do drive a lot of highway, i'd say my drive is 80% highway, 20% city. I didn't expect to get 35mpg out of it, i was expecting a little less, but hey is great!
As far as longevity goes, nobody has really had one for that many miles, so we can't really tell you. But Honda makes very reliable cars, and mine hasn't had a problem. I'll definiately be able to take this one past 300,000 miles with no problem.
Insurance wise, i didn't see that big of an increase. I mean with full coverage, my insurance went up about $900 a year over my old car. (which was a 1995 model) But that's expected since this is a brand new car, and i have a very high amount of coverage added on it. It's also registered for a young driver too, so that adds to the cost.
You'll love it though, the only reason i bought the LX over the EX was because i was planning on changing out the rims anyways and upgrading the audio, so the alloy wheels and 6 disc cd changer that come with the EX wouldn't matter to me. So i figured....Why pay $1,500 more for an EX when those upgrades will be changed anyways?