That is a very tough question.
As An alternative, I might also consider buying the 991.2 Turbo now, and later adding a COBB AccessPort or other, and tune. That would be faster than the 991.2 Turbo S.
JMHO...

he'll tune either or. I'm just wondering if the .2 improvements are significant

for non-performance related, very minor stuff - really like Apple CarPlay functionality in the .2 PCM, also the manettino toggle thing on the steering wheel is cool lol

As the old adage says, always buy the newest you can afford.

It depends on the options that he wants. If he wants it really decked out with options (centerlocks, PCCB, PDLS+, PDCC, etc., then the TTS is the way to go.

besides PCCB and CL aren't the other options on a turbo too?

If the 17 Turbo doesn’t have PCCBs, then go with the TTS. I couldn’t imagine going Turbo without PCCBs. But you should ask on the Turbo sub-forum.

IMO, most of the improvements of the Turbo S are in the PCCB and mild tune. Not enough to steer me into the older S, unless the PCCB are an absolute must have.

No. The TTS is more of an options package than anything else. You can option a Turbo with all the things that are standard on a Turbo S, but it will cost more than a Turbo S. The Turbo S includes PDCC, PDLS+, 18-way adaptive sport seats, leather backs on the sport seats, and much more.

Performance-wise those two models are quite similar- TT is down 20 hp but makes up for it with better PDK response, and improved turbo response.

I don't think there is much, speed wise, between the two of them. Frankly, I don't think there is much between a TT and TTS of the same generation. At least legally. I used to own a .2 TT and it was stupid fast.

Newer car = longer warranty and less wear. That's a good thing.

I do think the .1 is a better looking car than the .2. The newer Turbo has a longer, more pointy nose and a bigger turn signal unit.

had the same questions, i got the 991.2TT . im very happy with my decision 8 months later.

I don't want to over simplify - but from a performance perspective the 991.1's are easier to modify - simply because you don't have to remove the ECU and ship it to your Tuner. So if you are modding - I would go with the 991.1 - and you get all of the Turbo S hardware.

That said - I voted 991.2 Turbo (although the prices are pretty close depending on your upgrade list for a lightly optioned 991.2 Turbo S - more on that later).

The reason being that if you are keeping the car - you want to go with the latest iteration - especially with the 992 already out. Modding will catch up - someone will crack the ECU - and you get the .2 upgrades in the process. The 991.1's turbos are the same for both Turbo and Turbo S - so the modding path is the same - as it is for your 991.2 Turbo.

THAT said, you only live once - and the 991.2 Turbo S turbos ARE different for the first time. Not massively - but they are different. When I priced out the two cars - especially when adding CCB's to a Turbo build - they were within 9K Canadian (so 7Kish US) with the same options. If you can squeeze it out - I would go Turbo S - 991.2. If not - 991.2 Turbo.

Let's not forget 991.1 and 991.2 are both great cars - so you can't go wrong either way.

Good luck!