My two smaller front rings, chain, and cassette were all replaced at the same time but they have about 500 miles on them at this point. Actually this is the second chain. The 6061 grade aluminum middle and granny are just waaay too soft for this application and they are spreading laterally and getting stuck between the inner chain plates. Fortunately Surly makes a stainless steel 94 BCD 30t ring! I love the way you can find just about anything you need for nine speed systems, and at a good price. I've considered upgrading my drives system to 10,11, and 12 speed but the 3 x 9 is still better in my opinion. You aren't captive to a boutique proprietary system. The new 148mm Boost system is only 7mm wider so they have a TON of chain angle. There's no benefit from a gearing standpoint.

I like the idea of swapping between 3 chains at intervals to make everything last 3x longer. That's an excellent strategy. I'm thinking of running 8 speed chains on my 9 speed setup too. My cranks are from the 8 speed era and this new Surly ring is made for 8 speeds. The wider chain rollers will wear better and perhaps make front shifts more reliable too.