The E92 M3 is the first BMW I got and I love it but I also got a chance to drive an auto 335i coupe as a loaner for a day and it was pretty impressive itself in terms of DD power but to me the M is an overall better driving experience. The E46 M3 still turns heads, I still drool over seeing a black on black E46 M3, it is such a beautiful car and still is. If the E92 M didn't come out then I would've went with the E46.
If you're concerned about warranty then look into a third party that will give extended/ additional warranty on top of what you get. You may pay out a little more now for it but in the long term you'll be a little more at peace.