I use Mobil1 filters on both cars.

RX-7
Summer: 20W-50
Winter: 10W-40

Civic
Summer: 10W-30
Winter: 5W-30

IMHO, 20W-50 is way to thick for a piston engine in most environments. My local Acura dealer used 5W-30 year 'round in my old Integra, when I still had that (it was dealer maintained all of it's 167,167.7 mile life... freaky number to die on)

 

what are u talking about with the cardboard inlay or whatever, tell me why i shouldn't use it cuz i really have no clue i just know its what ive always used and i havent had ne problems

 

I changed my oil last week and used a Honda filter. The Honda filter looked like it was of better construction than my old Fram. However I can't really say the Fram didn't work.

 

Take a look here:
http://www.ntpog.org/reviews/filters/filters.shtml
This guy has cut up a number of filters and posted the results. IMO the important thing to note is that the ubiquitous 15400-305-POH made in Canada is the same thing as a Fram filter. I read something from Fram recently defending the use of those cardboard end caps. I also have friends who swear by Fram filters. I've never had one fail, but I'm not too crazy about having cardboard in there as the means of holding the pleats together. Since most of us change our oil pretty frequently, this probably isn't even an issue...just personal preference.
Bogatyr