F1 Dark is a great pot, but it is pretty slow. On a platform like 2011 or 775 where you need to keep temperatures within a range so you don't cold bug then this is the perfect pot for it. It will hold a chip at temperatures of your choice all day long without you having to pour like a mad man.
It is good for full pot benching too, but if you CB or CBB then get ready to say goodbye to some of that precious LN2. It's a pot with a lot of mass, so naturally it's going to take some time to cool all of that mass. It's fine if you only have to do it once at the beginning of a session, but if you have an Ivy chip or such that has a CBB but no CB, (they're not rare) then you're going to find yourself 'wasting' a lot of ln2 pulling the pot back down. Where as something like the gemini with a fast base will pull down in about half the time and still handle the load.
That's my personal experience, I don't own a gemini myself but I have benched with one before. The F1 is my own pot, and while it's great it does get annoying having to pull it back down if you cold bug. Luckily my best 3770K has no CBB.