I went to a sinn boutique to check new models as I've been considering adding a casual piece to my plexi 103, here are a few pics.
First the usual ezm3 and 3f (lower WR of 20bar vs 50bar, countdown bezel), the 3f cleaner dial is tempting:
Sadly the ezm3 doesn't have tegimented steel which I would rather have to avoid scratches, so I also tried the 857 and limited edition U50 DS:
The U50 DS was today's unexpected surprise, the lack of red accent makes it a very low profile, low attention getting model, although I wish it was a bit bigger. I also tried the new T50 and was shocked at how small it looked in person, I didn't even take any picture!
In the end I left with a new canvas strap for my old, trusty 103:
If you want the toughest watch around, get a fully tegimented U50. Or a U1 if you feel the size of the U50 is on the small side.
On the point of submarine steel: while it is harder than traditional 316L, it will still scratch unless you go for a fully tegimented model. On the standard U50 / U1, only the bezel is fully tegimented.
If you just want a more modern, more tool looking watch than your 103, then the EZM 3 / 3F would be the way to go. They are made of 316L steel, but the beadblasted finsih means that scratches won't show as much as on a polished model. Their look is distinctive enough from your 103, without being as extreme as the one of the U50 / U1.
I have both the U50 (fully tegimented) and the EZM 3F, and the U50 is the one I tend to take out for really taxing activities (tennis, gym, sailing), while the EZM 3F is a great everyday / travel watch that is also well suited to sports. I chose the EZM 3F over the EZM 3 as the extra 300m of water resistance are of no practical use to me (and 99.999999999% of people), the profile is slimmer by 0.6mm (11.7 vs. 12.3) and I much prefer the cleaner dial. I also find the red over black date of the EZM 3 very difficult to read, and if a watch has a date function, I want to be able to see it.