Apparently many people really do not like the "newer" and "hotter" crock pots. With the temperature being hotter, many people are reporting their food being burnt.
Thing is because most of the recipes are for the old style crock pots.
Is there a good rule of thumb when it comes to cooking with the newer and hotter crock pots? I bought an oval 6.5 quart (6 l) crock pot but I'm half scared to use it because I don't want it to get burnt.
There's no right answer to this, every brand is different. Plus, you are assuming that you will have this problem when you don't know if the pot you bought is hotter than normal. In any case as long as you have enough liquid in it and use a low setting you shouldn't have to worry about anything burning.
My advice is to try a standard slow-cooker recipe and see how you do. If it cooks too fast then try bigger chunks.
It is possible that the newer crockpots have higher power (possibly to get food out of the 'danger-zone' of temperature faster).
However, slow cookers are designed to work with water inside the pot and as long as there is water in there, the temperature should not exceed the boiling point of water (~100C/212F). So when you say that
people's foods are being burnt, it suggests that the water is evaporating too fast.
I do have one of the new Crockpots and find the 'high' setting only good for getting the food and pot up to temperature (first 20 minutes) otherwise the slow cooker feels more like 'passive-aggressive cooker'.
Go ahead and give it a run. But visit it a couple of times per hour and check on the water level. As long as it's covering or almost covering the food, you're good. You can adjust the starting water amount for next time (or add if things are dire).
If you have the digital one, it's nice to set the timer. So when you forget to take the food off and drive to work (me, last week) you come home to a non-disaster.
Not true. Try leaving pasta in for an extended period of time. It comes out practically nonexistent. So not all recipes can be left unattended.