The 285 is just over 11 inches wide so it's 1.5ish inches skinnier but they are very close in height. The width is the noticeable difference

 

The 285/70/17 is 32.71X11.22

Saying that my 285/70/17 Goodyear mt/R 285/70/17 are actually a 1/2" taller then my 33X12.5X15. The 33's don't even come close to 12.5" either. More like 12.2". So other then the 33's being a 1" wider it turns out to be smaller in diameter to the 285's I had.

Of course each manufacture seems to play with sizes too much. Non e seem to meet their claimed size

 

like others stated the 285's are about 1" narrower. I like the wider tire look on my JKU but it's your preference! Here is a pic to give you an idea on what a 33x12.50R17 tire on a 4.5" BS rim looks like.

 

And, for comparison sake, here are 285/75/16s which spec out same as 285/70/17s. Mine even came with a rabid squirrel / theft deterrent / recovery device. . Revy's scenery is much better however.

 

Revy's scenery is much better however.

True, but you've got that awesome hamster on a leash guarding your rig.

 

Metric tires besides the size's your comparing are generally going to be a D or E load range and cost more compared to the standard size's which generally C load range and cost less

 

Just measured my 285/70/17 Duratracs and they come at 31 3/4"D x 11 1/2"W (on the button).

 

Most chats for 285/70 17 have a 8.5 wide rim as ideal. approve 7.5 to 9 inch rim.

The 33 12.5 17 have a 10 wide rim as ideal. approve 8.5 to 11 inch rim.

I don't know how important that is. I would make sure I have rims that are at least in the approve range. I have 8" rims so would go with the 285's. I believe the 295's 70 17 call for the same rim. This would be a little wider and taller also.

 

The 285/70/17 should also give you a little better gas mileage, at 1-1.5" narrower, you have less rolling resistance.