Goodmorning can any of you sinn owning jents recommend a good service for my sinn please ?

Afternoon all …amoung other watches I love my SLA021 for many reasons however I intend to use it as my sailing watch , but the only thing that concerns me is the lovely bright deliciously polished case !..especially in say some of the more dodgy harbours .
Anyway I spotted recently that seiko had brought out a black version SLA035 I believe ..does anyone have any experience of this model especially with regards how the coating wears my mm300 is not a desk diver !.
I do own a sinn 856 which I have had for about 20 years and with its tagimented case apart from a couple of dings still looks great , so I have been considering prehaps selling the SLA21 and going in the direction of a U1 or EZM3 , but that would be a shame as I love my mm300 but I feel on the boat in certain places it maybe needs to be under the radar a bit more !…
As regards should I keep it anyway the thing is I am trying to get down to 4 watches which all have a purpose ..
Sinn 856 UTC daily wearer ..
Dornbleuth & Sohn 99.1 city wear .
CWC G10 . Heavy work wear .
Seiko MM300 ?? Sailing wear .

Yes i know as the title says however i am struggling to post images .. i am a flicker user and it used to be ok but now posting seems such a problem ! Any advice and no i woulld rather not use tapertalk if possible ..

Hello all I have an Sla021 MM300 rather stupidly I cut the rubber waffle strap down when it arrived due to it being very long on my 7” wrist and then realised later on it would not fit over my coat cuff when I was sailing and I bought it to use for sailing !
Anyhow I am wondering whether I should pay the extortionate price for a new mm300 rubber waffle strap “ it is very comfortable “ or purchase a crafter blue or an isofrane ?
Any suggestions much appreciated whatever else though it does need to be comfortable…
Many thanks in advance …