Here's a copy and paste from the Sinn forum, for your reading pleasure.
It is interesting to compare the U1 and the T2 together because even though they are similar, they are in fact very different feeling, very different wearing watches. Surprisingly so.
The U1 on bracelet feels robust. It is heavy, it is thick enough to be noticeable and with its flat sapphire crystal it wears like a diving watch should. On the wrist it feels strong, weighty, bomb-proof. The curved caseback is the key to the comfort of both the watches but the U1 has a large dome whilst the T2 has a smaller one.
I really like how the U1 wears. I have tiny, skinny, chicken-wrists but a preference for bigger watches. For a big watch the U1 is very comfortable and I don't think it looks too large on the wrist in person, though it looks pretty big in my photo below.
I love the lego-hands of the U1. They are iconic. I also really like the dial layout; there is a calmness about the watch. There is plenty of visible space between hands and printed indices which I really appreciate (although others might not). The lume is adequate, nothing more. Even on my new U1T it is still merely adequate. It can be seen all night long, but you might have to strain your eyes a little in the wee hours.
Yes, the lume is a little bit 'meh', but the watch itself is first-rate. It feels like it could survive a nuclear blast on the wrist and with a fully tegimented case and bracelet it is guaranteed to look good for years to come. When I wear it I can't help but look at other watches around me and chuckle with the knowledge that I could use my T1 to smash them into tiny pieces and still have it looking a million dollars. It is quite an emotional watch in that regard.
The lume on the T2 on the other hand is excellent. Really good. Maybe not Seiko-bright when fully charged but it lasts like a demon all night. The indicies aren't just painted on either, they are built up to be raised, composed completely of lume.
The polarising aspect of the watch is definitely the handset. I really, really like the minute hand. In fact, I think it is my favourite minute hand of any watch I've ever had. It is large but kind of organically curved. I am partial to arrow minute hands (not arrow hour hands - I'm looking at you Seiko tunas. Why have an arrow hour hand? Nobody diving needed to tell the hour at a glance so that they could rush to put the roast on for dinner. It's just silly) but less partial to really jagged ones. the T2 has the perfect curvey-sexy minute hand. I don't mind the hour hand but I think it could be about 1mm longer to balance the minute hand more. Still has that organic feel.
I realise the things that made me sell the watch when I last had a T2 are things that I don't mind now.
The first is the weight. The watch, on bracelet, is ridiculously light. It feels almost like a kids watch or a plastic watch on the wrist. That lack of weight makes it feel somehow more fragile. It isn't, but it can feel like it. It weighs less on bracelet than my titanium Bremont Endurance S500 (the watch against which the accuracy of all other automatic watches will forever be judged moving forward. It has had a variance of less than -0.05 sec per day for the last 3 months of daily wear. In that time it has lost about 2.5 seconds) weighs on a rubber strap. Plus it is 13mm thick. I have no idea how they packed 2000m of water resistance into a watch that light and thin, but they did. I don't mind the weight now. I did the last time though. Mine is keeping about - 2 sec a day.
The second is the dial. Not the hands but the prominence of the 12 o'clock mark and the slightly compressed feeling that I get from the whole layout. The U1 feels industrial, like a machine dial designed for a specific purpose. The T2 dial feels more organic. Looking at it somehow reminds me of a sea anenomie or a jellyfish. Don't know why, but it does. I feel pressure when I look at T2 dial, more rushed. I feel the opposite when I look at the U1 dial. It might have been different with the T1, having a bigger dial and case. It is important to note that neither the U1 nor the T2 dial seems threatening in any way. I could never wear a Seiko Monster, those pointed indicies remind me of teeth that want to grab and bite me.
Overall the T2 is great. It's a keeper. Yes, the clasp on the bracelet is pretty crap, but at least it is unobtrusive and hides well underneath a shirt cuff. It doesn't scratch your significant other when you give them a cuddle. It is the last diver that Helmut Sinn designed before his death and what he saw as the natural successor to the IWC Ocean 2000. There are some things that weird me out about it, but it is a wonderfully functional, amazingly well built little machine that fits my wrist like a glove.