I'm Happy to chime in on this and provide some thoughts and my personal experience.
Firstly if you are of the absolute belief that only a manual is for you then there really is no point reading on!
If your motivation is that you want the manual as it's a "Badge of honour" again don't read on!
So with those caveats set, I do not wish to go down the rabbit hole that is "PDK v's Manual" and the ensuring 30 page debate!
I have driven manual clutch transmissions all my life, auto's were always a compromise they were slower, less responsive, less engaging and an overall dull experience connected via a horrible torque converter. Yes some are a lot better than others but they all provide drive through a torque converter, so you are always going to have a "dulled off" experience.
I would NEVER consider an Automatic transmission for any sports car!
Friend purchases a new PDK equipped Porsche, early PDK example. Throws me the keys and says give this a try, righto not sure why you purchased an "auto" but lets go.
Well..... initially my impression was this thing is quick... real quick the changes are instant....it got my attention! Ok Porsche I'm now listening.
Play with this a little more and I recall vividly the first time I powered up Mt Donna, manual selection mode enabled, sports plus mode enabled the gear shifts are astonishing seriously powerful stuff. You keep your right foot planted, click up on the paddle and instantly and I really mean instantly you feel a firm push back in the seat as the car goes up a gear and once again returns the engine to it's optimal power/torque range, changing down is as instant with the added bonus that you cannot overrev the engine.
In manual override selection mode it allows a lot of control over the gearbox, however it wont allow you to break the engine!
My personal experience with using it in full manual v's "auto" mode is that the calibration that the engineers at Porsche have done is spot on. I feel and this is subjective that the calibration on the 981 is a little better than on the 987.2. I have found that I am less likely to engage full manual mode in the 981 than the 987.2, maybe it was because I just wanted to rev that sweet 2.9 that was in the 987.2 ! What I will say is that using the car in manual selection mode ALWAYS increases fuel consumption!
Since then I have purchased two PDK equipped cars and wouldn't consider a manual unless the model year range was a Tiptronic only affair like a 997.1 gen etc)
I would highly recommend getting one with the sports chrono package as it gives you the active engine mounts, sports plus calibration, launch control and a the chrono clock (which of the last two you probably will never use) In sports plus auto mode it is not really viable for use on the road as the shift points are so high and it is very much a track calibration HOWEVER in manual mode the increase in the speed of the gear change is alluring and quite addictive!
So what you lose is something to do with your left foot! Taking off from start is less engaging there is no question of this you simply don't have as much to do. When you come to a stop once again you have less to do and are less engaged in the process in both instances.
What you gain is a car which has Mutiple personalities, in standard mode it is quite docile and could easily pass as daily driver gear shift is quick but not violent etc, press one of the other modes and you see quite a change in personality of the car it simply become more aggressive. Throttle recalibration, gear shift speed increases, firming of the engine mounts all contribute to this feel.
Car in sports plus, manual override mode coming towards a corner shift down on the paddles INSTANT, through the corner, power down coming out, shift up no need to lift the throttle AT ALL instant gear change up again as you climb the hill throttle buried shift up NO LIFT on the throttle bang INSTANT CHANGE you get that shift and the violent push in the back .... this is what did it for me and continues to do so.
This has been my experience and I said I really do not want to engage in a manual v's PDK discussion. For many it is emotive subject that they have a very firm non-negotiable stance on and this quite ok .
Hopefully some of this is of use 😁