Clamp-O-Tron Sr. vs the large decoupler/separator

[Daiya]

In my travels within the Kerbin system, I like to use a copycat Apollo style Command/Service Module that I tweak from time to time:

I had been alternating between the decoupler, which is bulky and ugly, and the separator, which is more aesthetically pleasing but heavier, when I happened to notice that the large docking port was thin and lighter than both of the other ones. I flew a few test flights and found the port to work fine and I appreciated the little extra deltaV.

Am I missing something here? Will there ever be a situation where a decoupler/separator module would make a life or death difference to my Kerbonauts?

[King Arthur]

Decouplers/separators are sturdier than the senior docking port and also quicker to operate because you can stage them (latter is a non-issue if you action group the docking port, of course).

[maltesh]

The Clamp-O-Tron Sr allows fuel crossfeed by default, unless you switch it off in flight mode, so that's something to remember if you're going to use it instead of a decoupler.

[SkyRender]

The main drawback to the Sr. docking ports is their stress load tolerances: they suck. A lot. As in, if you exceed 2 G's acceleration during your ascent, they'll snap like twigs. You can still get a pretty good circularization without exceeding 2 G's, but it's something to be aware of.

[Guest]

I prefer separators as opposed to decouplers, in general because they look so much better. The weight difference in the large ones is fairly negligible. It's also really cool to see the ring separate from both stages and float off on its own.

[TheSaint]

When I designed my first Mun rocket I used an LOR profile, and I placed a separator between the LM and the CSM, thinking that it was the best choice since it would leave no residue on either of them. Unfortunately, I discovered that when I staged it and turned around to dock, it just sat there between the two, blocking my docking approach. I wound up using two decouplers back to back. Staged the first to separate the CSM from the LM, turned the CSM around to dock, after docking staged the second to free up the CSM engine.

I have had designs where the only option was to connect two parts with a large docking port. They were very fragile, I wound up using lots of struts around them to hold everything together. Even putting a large docking port against a decoupler is fragile.