Mechanically they are identical.
The only difference between the years is the paint!
The 08 has the advantage that when you sell it, it will sound newer. Though, honestly, the odometer is far more telling to any moderately informed buyer.
If they are both fresh from the dealer (near zero odometer) then go for whichever one you like the look of better. You can justify it as “getting the better deal” if you like the color of the 07, or you can justify it as “will have more resale value” if you like the color of the 08.