I think you need to try one then, the way people talk about the e39 M5, i think an e90 would be a good natural progression, although from what you say, the lack of torque below 2k rpm would be different to the e39, you do need to make sure of the box a decent amount in the e90. On the flipside, having just been down to Cornwall for the weekend, whilst it is epic letting it fully rev out to 8k+ rpm, it travels ground really rather well from 3-5k rpm and with the 2 pipe mod does sound wonderful. The noise under load in that rev range is sublime, lovely induction noise along with the warble/wail of the V8, my god does it love to rev though, the throttle response is magic even in normal mode, in Sport Plus its electric.
Its got plenty of space for 4 people and their luggage and cruises quietly at 80mph with a decent sound system & full iPod integration (the "base" sound system is also more than good, far better than in the M135i where it was terrible!), with the EDC set to "comfort" the ride quality is very good, with some slight firmness added in "normal", "Sport" will be set for when im by myself and the roads are billiard table smooth i think, the M Button is currently set for Sport+ throttle, Sport steering, Normal EDC and TC On, if i want MDM ill turn that on manually i think.
All in all, ive owned it for a week and done 1k miles over a variety of roads & speeds, both myself & with 4 up. Barring the slight thirst, 15 around town, 24 on the trip to Cornwall (compared to 27 in the e46 M3 and 31 in the M135i) and small fuel tank (just enough range to get from Weybridge to Penzance), i can safely declare (thankfully as its cost more than anything else ive owned), that its the best car ive had, quite easily.
It surpasses the wonderful e46. Whilst do miss the rasp of that car, the V8 sounds fantastic in a different way, more broad chested/deep and it just sings to the top end. Easier than the 6 in the earlier cars imho, it never sounds strained, similar to the vtec lumps in a Honda, it feels like if there was no limiter it would happily go far higher with no sign of strain or unhappiness. The overall usability and feel of the car is just that bit better than the older ones, but again, imho, better than the new ones, purely as the quality of the interior materials is just higher, perhaps the e92/e90 era was a great one as it matched the higher build quality of the e46's with the modern tech of the F30's, but without the penny pinching of the modern era, im not sure, but i do love the car. The perfect family car perhaps, but bugger me, it wont be cheap to own i dont think.