This 105 chain is the same weight as the Ultegra version, but lower price. I'm running with Ultegra R8000 cassette and R8000 crankset & rings. Inside running on Ultegra 6800 cassette on the trainer. Quiet, smooth, works flawlessly both outside and inside. Can't go wrong with Shimano. I'm not using the quick disconnect link that came with the chain. I find the KMC aftermarket quick link easier to get and off.
I have run the top three level chains from shimano, and it is tough to find fault in the 105 level. Lasts a long time and can survive through my laziness if not cleaning it often enough. If ultegra is on sale, go ahead, but my every day reliable option is 105 for chains and all other components.