My 996 turbo is a Tiptronic but my other cars (M3, Caterham 7, etc) are manuals. In the turbo, I went for a Tip because (a) it's b***** powerful anyway, (b) it suits the turbo engine and (c) mine's LHD (bought for Continental tours) so I don't have to bother teaching my right hand to change gear. Regarding the niggle of the 'delay' on gear changes, John Lyon (he of HPC fame) taught me the thing to do: learn to match the engine speed with the new gear speed using the throttle while operating the change button. It's a bit like heel & toeing, giving a slight blip on downchanges, etc. It removes your perception of delay and reminds you that the gear change is actually quite fast.
As you may have guessed, mostly I use manual mode, but the option of putting it into drive and being lazy when in traffic is just great, especially when in foreign cities and you're busy reading road signs, checking for one-way streets, looking for the hotel or such ... then you just use the kick-down if you need to swap lanes quickly. Easy.
To answer your question about parking, it's not a problem shifting between forward and reverse; the car is very well-behaved, as the engine doesn't tick over too high, so no clunking or lurching. It's a lovely box.
And you don't have to save up to replace a clutch.