If you liked HC-110 you should be impressed with Ilfotec HC. I appreciate the convenience of controlling contrast not only with time but also with different dilutions. You can also control its grain appearance with dilutions as well, basically the same workflow as HC-110.
I only use it for large format, which I shoot infrequently. So longevity is important to me. You can search the old threads, and you'll find that people have been saying for many years how similar HC is to HC-110 and how well it keeps. But what's amusing is that nobody shared their experiences with its shelf life. I have not found a single comment online saying
"it's been 5 years and I'm still on my original bottle of Ilfotec HC". Meanwhile nobody ever said
"I opened the bottle of HC after 2 years and it's dead". For some reason only Rodinal and HC-110 are cited in such stories.
Well... I am on my first bottle of Ilfotec HC. About 30% in. It's been opened for 14 months and it's going strong.
It is also readily available everywhere in the US and hasn't been affected by supply chain issues. It has always been in stock at numerous online stores and at several local shops in my area.
Here's the sample of HP5+, the primary film I shoot. As you can see, the tonal range is impressive and it holds highlights quite well.
One more thing: people say that HC-110 loses a bit of film speed. I have never used HC-110, but I have not changed my exposure habits after switching from Xtol to Ilfotec HC. I use box speed and meter either ambient light, or spot on shadows, just as I have always been with other developers. Did not notice any shadows issues. But I haven't done any controlled tests, so I don't know how HC affects film speed.