Service Coke vs. Tradeup GMT II ceramic?

[slumd]

First post! Have a 2007 Coke GMT II, originally running about +4 secs, now 8 years later about +7 secs. Bracelet a bit scratched up as well. Also have an '07 Sea Dweller and 2013 Nodate Submariner ceramic. The question I am having, is it worth the $800 service fee to keep the older, more casual Coke, or save the money and kick in extra to trade up to the ceramic GMT, probably BLNR? I do rather like the solidity of the new bracelets, but prefer the all-brushed style of the old. Also, I do like the color scheme of the Coke, though I like the look of the ceramic material on the new. Decisions, decisions!