How long to stay on the plant once turned colors: It depends on your individual preference and conditions. I've found a number of reds (hot or not) first turn a more red-orange before truly ripening to red. Waiting until they are fully red allows them to fully develop their sugars, which makes the pods sweeter. I prefer this fully-ripe stage if I am going to eat them raw, and even in many cooked dishes. My recommendation is to let them sit on the plant a bit longer than a couple days and watch to see what happens with the color. Then try a couple - one fully ripe and one that's turned but isn't as ripe. See which one you like better, or think about how you would deal with the flavor differences. Some people don't mind picking off the plant right away and then shelf-ripening - you're going to have to decide if this is an approach you want to take or not. If you have a lot of herbivores around, shelf-ripening might be the best option to ensure you get to eat the pods and not some animal.
Buzz: This is kind of a hard one to answer. There's a "typical" size that any given variety gets, so a pat answer would be once they reach full-size. However, any plant can produce pods that are smaller or larger than normal. I'd recommend keeping an eye on things to determine when a given pod is not growing any larger - pick it after you make this determination or pick it after it's just barely started to turn color. I've never seen a pod go from green to :BOOM!: red overnight - usually there's a part that starts to turn while the rest of it is still green. If you're not sure of a pod's "full size", this would be a good indication that no more growth will occur.
