DMF 

I was surprised in a nearby thread when the poster reported that his Silver Power Link formed a stiff link on his new Shimano 8-speed chain. I thought it was something unique to the situation. I and many others long have used the SRAM links on Shimano chains with no problem. However, today I tried to put a new link on two old 8-speed chains, one Shimano, one HKK (whatever that is). The link was very difficult to close and when it did close it was quite stiff. The SRAM link is obviously too narrow for the chains, but not by much.

Now, SRAM has long stated that their links are "for use on SRAM chains". Maybe the've decided to enforce that by making their latest 8-speed chains - and links - a smidge narrower than the Shimano counterparts. It would be a good marketing move by SRAM: How many Shimano chains are sold with SRAM links? If the links don't fit that chain, the purchaser is more likely to buy an SRAM chain - with link - instead.

Fortunately, Wipperman Connex is still an option.

Cyclist0383

I've had trouble with SRAM 8 speed links on Shimano chains in the past. I've had absolutely no issues with SRAM 9 speed links and Shimano 9 speed chains.

DMF 

So far, neither have I. But I haven't bought a new one in a while.

Cyclist0383

No need to panic, the old 8 speed ones didn't work with Shimano chains (at least the several I tried) either. There is no conspiracy afoot.

Raiyn

SRAM 8 speed never did fit Shimano 8's The 9 speed link works with Shimano 9's however.

DMF 

KMC MissingLink II works too.