I am planning to get new tires for my 19 OEM rims. A lot of people are recommending 245/35/19 front and 255/40/19 back. My only concern is the ride may be harsher with 35 in the front and the tire may look stretched as is it about 1 inch less in circumference than stock 225/40/19. How about 235/40/19 or 245/40/19 in the front? Any problem with these sizes?

 

The smaller sidewall isnt going to make the tire looked stretched as you are increasing the width of the tire by 20mm, the tire will look pretty square with a 245/35. Good luck finding a 235/40 for the front. You could run 245/40 front and 255/40 rear if you're worried about ride quality. Although i highly doubt you'd feel the difference between the stock 225/40 and a 245/35, its almost the same sidewall height.
-GP-

 

I just started running 245/35 and 255/35 on my OEM 19s and it feels pretty good.