Soulfood, as long as you aren't getting vine from somewhere completely sketchy (ugghh... it does happen), that's GENERALLY the rule of thumb. Yellow vine provides a very balanced experience, though it can get quite strong, so don't underestimate it as a walk in the park. Your experience will not be LESS, it will be BALANCED: body load, visuals, mental taxation, length of journey, taste, harshness on the body, etc.
Cielo... I basically had a few drops in my mouth, and it was so bitter (smells COMPLETELY different when cooking, like bitter almonds), that I literally COULD NOT take the shot.
I purged violently through my nose and voyaged for about five hours, with visions so powerful it made me question the purpose of adding DMT to a brew at all. I was shown a tree, and told that I was not ready to learn the secrets that Cielo protects.
That was a year ago.
Recently, I got my hands on some more. Cooked it... haven't gone down the rabbit hole yet.
My personal favorite is white vine. The bodyload is less and it's very psychedelic.
Black vine feels like more of a body trip.
Red vine is good for healing.
Bali is much like white, but smells like Christmas cookies while it's cooking. Mmmm. Snickerdoodles.
That being said, there is much to be told about the smell of the vine while it's cooking. You will know if you have the kick-your-ass Cielo... you will smell it. There will be no doubt in your mind. Especially when you reduce.
Some things will come easy, some will be a test