I'll add my 2 cents....
I went from the ed30 to a mk7 GTI to a F36 430d Gran coupe (to a G20 M340i to an e92 M3). The 4 series are setup sportier than the 3 series and are also better specced. The *35d's are a lot thirstier than the rwd 30d's for not a lot more performance. I got the dealer fitted M Performance power Kit (New ECU & bigger intercooler). It dyno'd 313bhp and 479 lb ft on a tough dyno. It was on a dyno day where no stock mk5 made more than 202bhp. Traction isnt an issue either once you put decent rubber on the rear. The steering is completely lacking of feel, but feel isnt as important on them as a golf because they are rwd and dont understeer.
Also bear in mind that 3 and 4 series of that generation only get SE suspension with xDrive. BMW never made M sport suspension for xDrive cars, so they all sit higher and wallow more.
Thanks for that, much appreciated
Funnily enough, I had a good drive of my bro in-law's F31 320d (M Sport flavour) last weekend to see if it's actually what I want before going through the aggro of car shopping. It was also the perfect opportunity to drive it on the worst of my local roads that the ED30 crashes all over the shop on, and try it impartially without the new toy blinkers on.
It really impressed me to be honest. Yeah the steering feel has all the life in it of a corpse but the PAS weighting is loads better than the ED30's, which to be honest isn't exactly bursting with feel either. Very decent drivetrain and ride quality, so I'm definitely in. I'll be going for the 30d though as the 35d scares me maintenance wise tbh, and as you say, it's mpg is lower than I'd like. I'll look into the 4 series as well.
I like the idea of a proper BMW approved power kit. Can that be fitted to used cars or was it only available as an option when new? Every marque has it's shady back street remap stories, so that sounds ideal.
I also need to look into a proper VAG-COM equivalent for BMWs. I want to make sure the car I buy has never been remapped, which is an easy check with VAG-COM.
Sorry, I dont be on here much anymore, did you purchase? The power kit can be fitted to any car, regardless of age. It includes the intercooler from the 35d and a brand new ecu (dont know why).
For basic coding, bimmercode & bimmerlink work well. Yo just buy a wireless dongle and do it through your phone. Esys is more advanced but you only need that if doing retrofits.
@kevinm No worries. Makes sense you're not on here much if you don't have a GTI anymore
Yeah I ended up with a 2016 330d M Sport with 38k miles on it. It came with Harman Kardon, Blue M Sport brakes, 19" rims, LED headlights etc etc.
You're right about the steering
The lack of feel can be fixed easily enough, apparently, but it's not a deal breaker for me. Some of the steering crapness was down to the runflats, which I binned in favour of non-runflat SportContact 7s. What a transformation! I've experienced crap tyres ruin a car before, but not to this extent.
Power wise, I'm happy with the stock 258hp or what ever it is for now, but cheers for the info. In sport mode it's surprisingly thrusty for a diesel, but I leave it in Comfort 99% of the time. Haven't used EcoPro yet and don't intend do, but in comfort it's averaged 48mpg over the last 4 months. Not far off double what I was getting from the ED30
Bimmercode and Bimmerlink have paid for themselves already with disabling start/stop and coding/registering a new battery