The one that fits your winch
, is made by a reputable company that can provide real test Certificates and is a Grade 30 or 40.
By 'reputable company' I mean a known chain maker. You'll see chains and many other boat items tagged with a known brand name but they don't make them. As an example you see lots of Lewmar
brand ropes and chains but strangly Lewmar
doesn't have any rope
or chain making facilities. They are only selling you the 'brand' rather than the product, which most often comes out of the East. That's the latest and greatest thing apparently, don't sell a product just a brand. There are many examples, Nike, Tommy Halfinger, Rocna
, Lewmar, West Marine
, many car companys (a small Ford is actually made by Mazda), Murcury Outboards (small ones made by Tohatsu) and how did I forget 'Brittany Spears Perfume'
Not saying their products are bad even if Brittany's just doesn't work for me, but you just don't know who is actually making the product so there is room for uncomfort shall I say.
Being in Seattle
I'd say Acco (now Pearson
Acco) would be a good choice and at the same time you can have a few warm fuzzies from supporting a local manufacturer. Their 'BBB' is a Grade 30 and the Grade 40 (the HT) is strangely a Grade 40
The Grade 40 thing is huge in the US (nothing wrong with that) but most cruisers from the rest of the world are most likely to be on a Grade 30 (new name is Grade L). A well made chain failing is rear. Generally the chain makers make a stronger product than the anchor maker can get as a holding load, winch
makers, so one of those usually fails long before the chain gets stressed.
I'm excluding Asian made chains as they are usually made of soft metals so stretch real easy and are poorly, if even at all, calibrated. Also they do tend to have somewhat suspect and 'interestingly' written certificates. The random lemon factor is still way too high to make most comfortable.
Unless you have a real specific desire to have minimum weight in your locker and yet big strength I'd stay away from grades higher.
Contrary to many people thoughts, higher grade chains do not weight any less than lower grades (OK there maybe a ounce or so per foot but nothing big) but do have some big downsides. These being cost, far larger dislike of shock loads, next to none or none at all warning of imminent failure and they can't be regalvanised by 99.9999% of the worlds galvanisers. The '$$ per foot per life time' ratio is very poor.
A quick twist in the tail. If you're planning an extensive offshore
it may just pay to try and match your gypsy
and chain to the world standard sizes. The US runs it's own standard and while that is perfectly fine it does mean most US aizes are uncommon outside of the US. The Grading system is the same just not the phyisical measurements. But on some sizes there are equivilents that can be used. A 3/8" BBB Acco chain can be used on the same gypsy
pattern as a 10mm DIN766/A standard for example. A 5/16" G40 Acco can be swapped with a 9mm DIN766/A as another. But not all sizes have options.
Oh and the Aussies have there own sizing as well. Again there are the odd cross-overs but not on all.
suffered info overload and exploded yet