If you think the 335i has lag then you must be an impossibly hard marker. What do you want? A supercharged 7-litre V8 in a Lotus Elise with extra low gearing?

I use to tune turbo's when I owned subaru's ... (WRX STI etc) ... when you tune a car like that you iron out lag pretty quickly.

I have a friend who did a remap on his 335i and it is a definite improvement ..I think the problem is that like most mass manufactured cars these days (yes, even BMW;s) the engineers try to strike a balance in terms of smooth performance / economy ... and in some cases its even worse as they apply a broad-brush factory tune to all models that's just plain sub-optimal ... (except M's of course - they get special attention)

If you can tune an STi to have no lag then you are a genius... I didn't realise you are a car engineer. All the WRXs I have driven, STis included, are lag city compared to the 35i.

APS kit ... no lag. I'm not an engineer .. but my father is. We use to track it. bog standards STI is definately laggy ..no denying that.... in fact WRX standard feels better (until you hit a corner) ... subaru lost thier way over the last few years ..so ditched them ...

Track driving is a completely different thing to stop-start road driving.

What some may be experiencing is not "turbo lag" but second gear starts due to the way the engineers programmed the car for fuel economy and the new 8-speed transmission. As stated in the review entitled 10 Things You Should Know About the 2011 BMW X5... "Our only complaint involves the new transmission. When in Drive, it is programmed to start in second gear, which can lead to some sluggish launches."

Maybe this explains it? I have not test driven a 2011 X5 50i so I have no first hand experience.

laggy in comparison to what?

I would like to give that a spin:D Anyways I haven't driven the 2011 x5 but I did get a chance to drive the 4.4 tt in the 2011 550i and I did not notice any lag whatsoever. In fact the low end power is nothing short of spectacular.

I suppose the only way for me to really know is to test drive new models ..they should land demo's here in few weeks ..I've told my dealer to reserve some slots ...

I drove the 50i, 35d, 35i and my own naturally aspirated 4.4i the same day - http://www.xoutpost.com/bmw-sav-foru...ives-long.html.

I noticed some hesitation/lag off the line in the 50i. It wasn't a big deal but something didn't feel right. There are a bunch of things that could be at fault if it wasn't the turboed engine - it's possible I started in 2nd (though pretty sure I was in DS), the car only had a few miles on it and those 20" wheels didn't help.

This is only from a 30 minute test drive so I'll have to take the word of folks that have driven it for longer but as always, I recommend everyone decide for themselves with their own test drives rather than taking the word of anyone on message boards.