I’d not say it’s unreliable but it has minor issues if you don’t tune it and drive it hard it will be fine but the issues on the engine are well reported on but as all things it’s rare. As the M2 is a fun car and the Mrs uses it a lot the N55 was the better choice for us and I prefer the sound and as I was not too fussed about having fastest available as for speed thrills I’ve got the McLaren the older M2 made more sense for us but it’s got plenty of go.
The newer versions simply used a real M engine out of the previous years m3/4... I wouldn't say the N55 is more reliable either, they are known to be the opposite especially when tuned, they get VERY hot even stock, and love to go bang even on stock power, the internet however will claim they're the modern 2jz, just like they're now doing with the b58...
Having had 5 beamers and used them all for drifting, I will say they simply do not make them like they used to, stuff is made to just about last the warranty then the main stealer will con you for sod all in a trade in and simply bang a new engine in the minute you leave the door and chuck it back on the forecourt for a horrific price and so forth, you've only got to look at how bad the metal/paint used is these days - that's why they offered that no questions asked bodywork/paint/rust fix on all cars under 5 years old with or without warranty just ring up we know we F'ed up bring it in... Major lawsuit spec...
But as with any M car from the last 40+ years, it'll have loud tappets, the bearings will be shot in no time and score the crank which requires you to buy 3 engines to find 1 good crank/make a frankenstein because someones claimed the 1st and 2nd engine have a good crank/compression etc etc when they don't, use loads of oil on any revised version, require multiple parts/servicing over and over in very short intervals forever, do stupid things like crack the rear boot floor/rip the rear trailing arm mounting points out/require reinforcements on both, not bleed properly when changing coolant even lifted up at stupid angles, recommend the wrong oil from factory etc etc...
It's happened on pretty much anything, as with having the valve clearances done frequently, but that's the price you say for such wicked engines 'whilst' they work! All whilst cracking basically any set of wheels they come with regardless of tyre profile size!
Then when all that's sorted, in 30-40k miles, you'll do the bearings again, and the valve clearances/tappets at 9-14k
but you'll love the car more because you're so financially invested/bankrupted by it at this point, so when it works you appreciate it more
I swear people that buy new cars just smash into every pothole they can find on purpose and batter all their suspension/geometry, then call the car rubbish when stuff needs replacing! That's definitely the difference between buying outright vs lease/financing/enthusiasts/maintaining your own vehicle...
I've always loved the M2 as imho it is THE only modern true old school bmw IF manual (well as close as a modern car can feel like an old one without being a fat pig/awful electric everything) and is the correct size a car should be vs a 3 series now being the size of a 7 series from the 2000s and weighing 2 tonnes! The M2 IS the secret M3 in a dress, if you get the one with the m3 engine then no one can say otherwise, however that new disgusting looking thing is just rank, as is pretty much any of the new 'china wanted this styling/crappy lagfest torque converter rubbish gearbox over tried and test dual clutch 8 speed zf' modern rubbish!
Oh and FYI this is coming from someone that's worked for bmw and still loves them (the older stuff anyway) so I have no bias
Nice car though man, I member when they came out at work, we had one of the lads revving one and the manager came over and said get out (everything thinking the lads now in trouble), the manager jumps in and holds the button down on the exhaust valve and goes "this is how you do it"... and yeah Glorious noises 10x as loud haha!
Oh and it goes without saying THE best looking bmw ever made is an E9... Fight me!