Sooo I have to say my first experience with Tegaderm has been excellent.
I ended up taking the the first one off on Friday last week in the end, 'cause I had a major water breach while showering (to be fair I know now that I should have patched it as soon as the derm started to roll up a little on my wrist). The tattoo was very wrinkly and tender and so very, very dry at this point that I decided to wrap it up again to avoid having to deal with it over the weekend.
This proved to be a super smart move since I've spent the last six days puking my guts out and sweating off a high fever on a 5-6 times per day repeat cycle so I really wouldn't have had the energy to baby the tattoo at all (on a side note, got a nice relaxing morning of bloodwork, being attached to a drip at the hospital, some meds & happily no one wanted to blame the tattoo, and am well on my way to getting over whatever I had now :)).
Yesterday I finally took off the derm since I was feeling better and getting bored with resting, and just had a few small pieces left to peel and the rest of it is looking nice and lizardy. Not tender at all any longer either, it really feels healed now and also there's no dry pulling feeling like I had with the other arm unless I was lotioning it like every couple of hours during/just after the peel (that was at about the 2,5 week mark or so). I've been applying lotion only once per day, and it will be two weeks old on monday, so not bad at all especially considering that it probably wasn't the best healing conditions ever due to the immune system overload since I was so ill.
I'll post a pic with the progress later.