Sinn 104 accuracy brilliant

I think the more impressive part is the lack of the beat error, and the consistency of the reading. 

Did you have it regulated, or it just happened to come that way? 

My Sinn 104 StSa is almost +10

All Sinn watches are thoroughly regulated before they leave the factory. That’s why Sinn have such a great reputation. 

Mine came that way I also have 105 UTC which runs at -3 spd

I got my Sinn 104 exactly a year ago.  It was running -35 to -40 seconds out of the box and I had to send it back to get it regulated.  Once I got it back it was pretty accurate for about 4 months.  Lately it had been running -4 to -5 seconds per day.  

Slightly disappointing experience for me so far.

I don’t understand why you are disappointed as Sinn do not use Chronometer COSC spec movements in their watches and if they did you’d have pay considerably more. COSC spec is -4 +6 so your watch is running almost at that parameter. You have no cause to complain

The disappointment was the -35 to -40 seconds out of the box.  Also the customer experience when I had the issues left a really bad taste in my mouth.

I can understand your frustration. I think a lot depends on the AD your dealing with. We have a couple of good ones here in 🇬🇧 UK

I’ve a 556 and a 104. Got them both about 2 weeks ago. 
The 556 is running about +5s/day and the 104 +10s/day. Very slightly disappointed with the 556 but more so the 104. 
Will the 104 improve over the next few weeks? Should it be returned for regulation?

Are they both brand new unworn? If so give them a month or so to settle down and things should improve. My 104 is 6 months old and has only gained +3 seconds in 10 days. My one year old 105 UTC is even better losing just 4 seconds in 20 days!!! 

My Sinns are the most accurate watches I have ever owned, out performing COSC watches I used to own inc Rolex  

Yes both brand new. As you suggest I’ll give it a month then fingers crossed accuracy might improve Especially the 104. 

104 returned due to quality issue with crown. The accuracy remained ’poor’ at about +10sec/day. Got a 103 instead. At present this is running at about 5 sec/day which although not great is acceptable to me. My 556 is running about the same. 

Sorry to hear this. It’s so unusual to hear about quality issues and average accuracy associated with Sinn. I have had my 104 on my wrist all December and it’s only gained 1 second in that entire time. My 105 has similarly crazy accurate. Good luck with your 103

Not having much luck with Sinn watches. The 103 has had to be returned due to similar crown issues I had experienced with the 104. 
I decided to give a 104 another chance, this time a white dial. The crown operation is better but not perfect (when, for instance, compared to my Christopher Ward watches which are a dream to operate). The month old 104 is running at about +15s/day which is disappointing. I’ll run it for another month and if no improvement I’ll consider getting it regulated.  
 

I haven't put my 556 on a timegrapher, but I can say it is by far the most accurate mechanical I own. It usually runs around +/- 1 or 2 seconds a day.