Background
All right I suppose it's time to give some input on this match up since I'm 1 month and 1000 miles into the M340i xDrive and also own an E92 M3 (for sale!). I owned an E90 ZCP M3 and regretted selling it in 2013, had an M235i xDrive that I absolutely loved but felt it lacked excitement and was a bit on the cheap side. So the itch for another S65 in my life was too much and I picked up my current E92 in early 2018. Since then I moved closer to the mountains and between PNW weather issues, commuter traffic, and terrible roads, I decided to move on to something softer and AWD.
My E92 is a ZCP with M-Performance exhaust, stage 1 tune, DCT tune, Euro MDM, PS4S tires, and stock suspension. It is incredibly rewarding to drive on the freeway and back roads but I personally find it frustrating in traffic and bumpy roads, which is quite a large percentage of my driving. I also find it dated on the interior (although not bad for a 2007 design!) but the exterior is completely timeless IMO.
I ordered the G20 in Tanzanite Blue II over oyster leather with premium and exec pack, adaptive suspension, blind spot monitoring, HK audio, power trunk, spare tire, and PS4S tires wrapped over 792M wheels. No autopilot gizmos for me on this car. I think it looks the absolute business and is to me a massive improvement over the F30 both on the interior and exterior. Quality throughout is very high for this price point. I also found that I actually
like the cerium gray trim and badging, especially on this color although the downside is that it waterspots at the drop of a hat. I will not be paying out for black trim pieces. It should be noted though that this is a large car and the 3 series is no longer a small thing. I find it more difficult to park due to size but don't notice this much while driving at speed. The upside here is that interior space is excellent including rear seats that comfortably fit adults with plenty of room.
Driving!
If you've never driven an E92 M3 in anger, you must do this before you die. It is not the fastest or most powerful car but it is an experience like no other when you keep it on boil and know what you're doing. It is an incredibly responsive driver's car that has limits way too high if you want to remain reasonably safe on the street. If I'm not stuck in traffic, I'm usually redlining and pushing the limits at every chance I get. There are a couple of problems though. DCT auto modes either keep revs too low or are clunky in more aggressive settings. So just shift manually then of course. This leads to other clunky issues and generally the DCT is good but not great in daily driving. The car feels great for around town at 3-5k RPMs and becomes a monster at 6k+ RPMs. Never drive below 2k and keep it at 3k most of the time. This car takes work and speed to drive with satisfaction. It also has a very firm, sometimes uncomfortable suspension. It crashes over bumps, potholes, cracks, and road turtles more than I like.
The M340i xDrive is quite the change in driving experience compared to the M3 but it is objectively better in some areas and subjectively better for me in many areas. Overall I feel it is as capable or possibly more capable when it comes to performance on the street. It is not as razor sharp but it is easier and vastly more comfortable to drive at slow speeds and at street limits. Power up to 100 mph absolutely goes to the M340i. Beyond 100 mph is probably a toss up. This thing is a torquey rocket with very minimal lag power that is about as linear you can get in a 3L turbo. What a joy this engine is with the only thing lacking being noise. It's so good I don't really miss the S65. Never thought I would say that.
The 8AT transmission works expertly in any drive mode. I have yet to have a moment that I thought "huh why did it do that, I'm disappointed". The M-performance xDrive experience is very near RWD but with the traction and stability of AWD. Turning on "traction mode" (MDM more or less) allows sideways action if you want it but mostly it just hooks up with my PS4S tires. I can take high speed corners with more confidence and speed than the E92 M3 and it feels nearly as flat. I also can rip off the line in the wet which is something we deal with a lot here. Lane changes and cornering feel darty as they should and while not quite as sharp as the M3, there is very little difference.
Regarding the tech, not much to compare here. The M3 has bluetooth streaming audio which was the big deal 7+ years ago. Nav works but it's dated. Rear parking sensors, yay. So the G20 with all the tech gizmos (I didn't even go for driving assistance functions) is quite a pleasure to use. I especially like the surround view cam with parking assistance options, headlamps with laser light high beams that will blow your mind, M-HUD, and the interface between BMW and CarPlay infotainment. This car has top notch tech for the times.
Complaints?
So what is there to complain about? Well two things have perturbed me although the jury is still out if I would call them annoying yet or not. The steering is leaps and bounds better than the F gen 3 series or 2 series but in sport modes it is overly heavy and somewhat fatiguing. It is accurate and solid but of course lifeless as most EPS seems to be. All in all though it is good steering and not a major complaint. The other issue I've noticed is in selecting drive modes. There used to be a nice rocker switch for comfort-->sport-->sport+ which was tactile and easy to hit blindly. Now we have a flat panel and you have to press the sport button multiple times to cycle through sport, sport individual, and sport+, then a different button for comfort. The drive modes work great but it is tedious accessing changes, especially when you're used to an M button. So there you have it. Two complaints so far.
Conclusion / TLDR
The E92 M3 is a special car to me that I have just outgrown. If I could keep mine as a third/weekend car, I would, but I lack garage space and financials to do that so it's up for sale. The M340i xDrive hits all the boxes of a very fast, capable, and comfortable road car for daily driving duties and I find it a much better vehicle for every day use. For on street performance it is not a downgrade and in some areas it is a performance upgrade compared to the E92. For ease of driving and comfort it is an upgrade of several levels of magnitude over the E92. I know, not a shocker there but for a car that will probably dust an E92 around town and still be this rewarding and comfortable? That's impressive.
I'm sure there is a lot more to talk about with this comparo so let's hear other opinions too. Thanks for reading!
