First of all, Welcome 
No options are going to make you any real extra money when you come to sell. Just choose what works for you. Personally I only ordered the rear view camera this time because I thought it may make reversing down my drive a bit easier but have found it to be a really useful piece of kit (and Cheap too :whistle:o) and was one of the easiest choices to spec again. For me Dynaudio is a must. I have had it on my last three cars and can't see me unticking that option anytime soon. I am not a massive fan of leather and the Kings ransom VW ask for it made leaving that off very easy. I had DCC on a Scirocco and was really hovering over that but in the end didn't and to be honest I have not missed it at all.
Just go with your instinct/finances you are buying the car for you. No one else !!
I'm sorry but I disagree with Dynaudio I find it to be well, pretty poor. The bass from the boot subwoofer isn't deep enough. The sound gets very distorted at anything over quarter volume with the authentic setting and with the dynamic setting the bass rattles the door panels so much that it makes your car sound like some cheap crap. I'm really, really not impressed with Dynaudio and trust me i've spent days and hours trying various different settings, moving the volume to the rear, to the front, middle, turning bass up and down etc etc and just when I think i've got it sounding reasonable it seems some song will come on that makes it sound terrible again! I will definitely not be speccing it again in the future. I'd go as far as saying that the standard sound system in my MK5 sounded better, atleast that could handle higher volumes and still sound brilliant.
I agree with the Reverse Camera. That's like what? Less than £200 and is really useful and you also get to show off every time you put it in reverse. Can get a lot closer than you would have dared to get to objects even with the parking sensors giving a long beep you still have a good 6" to go back! No brainer to spec that and I would certainly have it again.
I also agree with DCC. I spec'd it and to be honest? It's crap. I just end up keeping the car in Sport mode now anyway and very occasionally maybe comfort but if i'm being perfectly honest I don't notice any difference whatsoever. Loads of people on here will tell you that the difference is huge and the suspension really feels better etc etc. But I can't say i've noticed. Yes maybe a little difference but not £1000 worth of difference. I won't be speccing this again either. The Stig on Top Gear got the MK7 GTI around the track quickest in Comfort setting too, so no difference performance or arguably handling wise there either!
Keyless, now I didn't spec that but I regret not doing so. It's cool to have the Push to Start button and certainly gives it a more modern feel. I will be speccing that next time for sure.
Performance Pack makes a lot more sense than DCC and in my opinion is a must for the same money. The bigger brakes not only look great and make the car look more mean but offer much better stopping power and if you ever go Stage 1 or above you can be confident knowing that the PP Brakes will comfortably handle 300BHP. (Same brakes as used on the R). Then you also get the limited slip differential which is BRILLIANT, i've never experienced anything like it. With the diff on and in sport you can literally turn in, wait for the car to settle in the corner and then plant your foot down on the accelerator and the car just grips the road like glue and catapults you around and out the corner with no oversteer at all. Amazing. And if that's not enough, you get 10 extra BHP as a bonus

Sunroof, i'm sort of 50/50 with this one. I think it adds more to the car cosmetically than anything else. It breaks up the roof brilliantly (especially since my car is Tornado Red) and looks great from the outside. It also looks cool on the inside to have the sky above you and is very nice in the summer in as it lets in more light and you have a blind to pull over if you prefer to drive in the dark. But from a practical point of view....hm no, can't say it's really been useful. I found it more effective in summer and fuel efficient to close all windows and the sunroof and put the air con on. Was like a fridge in there in no time. Would I spec it again? Part of me wants to but it would just be for cosmetic reasons. I would rather spend the money elsewhere.
Discover Nav - Yeah it's not the best Nav i've used, the RNS510 in my MK5 was better in my opinion. BUT I have used it a lot and it has got me to my destination countless of times. If I was to spec again I would go for the Discover Nav Pro as it has a bigger screen and the 64GB SSD Hard Drive built in but it's just a shame about the much bigger price that comes with it. I would have the Discover Nav or Discover Nav Pro again though, definitely!
Winter Pack - I had it on my MK5, didn't spec it this time. Firstly if you are having cloth seats then they never really get cold or hot, that's the great thing with fabric and if you spec leather (which i'll admit makes heated seats useful) then they come as standard so again no point in speccing the Winter Pack. Do I miss not having heated seats? No, not at all. Even in these cold temperatures with had lately the seats have never been cold to sit down on just the air in the cabin! I'd never spec it again unless I had leather and it didn't come as part of the leather package.
So if I was to spec again I would spec the following;
Performance Pack, Discover Nav Pro, Keyless, Reverse Camera and maybe High Beam Assist (Kinda Cool) and that's it!
The leather is cool but the price tag is ridiculous for it and the GTI cloth seats are excellent quality so don't regret not going for leather at all. If I had an R though I would probably be tempted to spec the Carbon Nappa Leather seats as the standard grey cloth ones look a bit....grandad like. (Don't shoot me guys! I'm sure they're very comfortable

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