In my previous comparison last week on the BMW 135i vs Subaru STI I have shared some of the pros and cons in my opinion. Since both the BMW 135i and 2008 Subaru STI are not out yet, I thought it would be interesting to see where the BMW 335i stands against the 2007 STI.
My article has been posted on 1addicts.com and "ducati", a member there, has done an amazing analysis, complete, detailed and very informative. He definitely knows his stuff.
No one really knows what the 2008 Subaru STI will be. There is some possibility of "softening" of the WRX degrading the raw brutality of the STI.
We also, of course, have no idea what the 135 will be like in the real world–IMO it all rides on the suspenders and the effectiveness of the DSC+ "e diff." The rest we get in the 335.
Subaru STI Advantages:
1. AWD system with 3 LSD's and an electronically controlled center diff (yes it has 4 diffs) has more grip than any RWD car will. This tremendous grip can be put to use on the varying road surfaces of the street, making it very, very quick in the real world.
2. Suspension is very well-sorted for the road. It's stiff, but surprisingly comfortable.
3. Handling is quite neutral IF you drive it as an AWD car needs to be driven (which is to say, differently than a RWD car).
4. Brakes are VERY good, and track ready out of the box
5. Tires are very sticky, track ready out of the box but still very useable on the road.
6. Car has a very raw and purposeful feel to it, which makes it quite engaging to drive
7. Engaging power delivery. You have to chase it a bit, as it doesn't come on hard until the midrange. But it hits hard and hangs on. It feels very quick, and it's fun to hammer.
8. Flat-four motor sounds great, if you like the uneven backbeat of boxers.
Subaru STI Disadvantages:
1. Exterior design and "JDM tuned" look. You either like this or you don't, but suffice to say it does attract attention of both the wanted and unwanted variety. Not as much attention as my old Phoenix Yellow Type R Honda, but enough.
2. Interior design is very 90s Japanese. If you liked late-90's Hondas, this will make you feel at home.
3. Interior materials quality is durable but not touchy-feely. BMW does much better here.
4. Interior is mixmatch. Neat red electroluminescent gauge package with green center stack lighting. No lighting on all 4 window switches. Nice seats with crap headliner and cheesy visors.
5. Car is loud. Gearbox whine, diff whine, road noise, tire noise. For some this would be a serious negative.
BMW 335i Positives:
1. Spools much faster than the STI, power is all there just off idle.
2. RWD is seriously fun if you deactivate DSC. Tail-out cornering is easy to access.
3. The car requires more finesse than the STI. RWD with big power is like a dance–easy inputs here and there to maintain traction, while you rotate around like a ballet dancer. Drive it heavy-handed and you won't make much forward progress. STI will allow more heavy-handed shenanigans.
4. Steering is more linear and predictable–the STI with its DCCD in Auto can change midcorner, sometimes multiple times (manually setting DCCD changes this behavior, though)
5. Exterior, if you like BMWs, is great until you get to the rear. Even with the Pontiac rear, I don't think anyone will say the STI looks better 
6. Interior shows much thought; from the soft orange/red overhead lighting, to the backlit switches, to the design. It's nice to be in. Some find it not as nice as VAG products, but I liked it.
7. Yes, I squeeze dashboards, and yes, BMWs is much nicer to squeeze.
8. 335 is MUCH quieter than the STI–you can enjoy that nice Logic 7 in serene surroundings.
335i Negatives:
1. Power delivery in one fat smooth push, seriously quick but not as much fun to access.
2. Accessing tail-out mode can be hairy without LSD. The car isn't always predictable, and this makes you dial back a bit more than you could on the street. 328i is more accessible, as it doesn't overwhelm the rears so much.
3. Brakes are not as powerful as the STI. Supposedly easy to fade on the track, unlike STI.
4. Car is too quiet. Not much engine or exhaust sound. Is this a performance car, or a luxury car? Where's the bark? N54 sounds a bit agricultural here, I think a noise booster or better intake/exhaust tuning by BMW would help.
5. The drive isn't as engaging as the STI. There is a lot to remove the raw road feel and experience that many enthusiasts find so addicitive; from sound deadening, to softer suspension, to more isolating and flexy bushings. Make no mistake: the 335 will haul. But it isn't constantly asking you, BEGGING you, to haul. It's a little.. Dare I say… Yes I will… Boring.
In short?
STI: Brutal, engaging, loud, full of character, all about the drive.
335: Stylish, comfortable, balancing sport with luxury.
Hopefully, IMO, the 135i will rectify the disadvantages, although I've hedged my bet with the STI. If the 135 shows up with a killer suspension (I mean SERIOUS not the 335 "sport package" stuff), killer brakes, and please dear God in Munich Above give us a LSD at some point… I'll buy it. The STI is ugly and has a craptastic interior. It's all about character and brutal speed. I'll take the more balanced BMW if we get a more focused version, more like the STI than the 335 (way more…).
