Canned coconut milk PROS:
Medium Chain Triglycerides
Anti-fungal properties

Canned coconut milk CONS:
Often contains BPA (some claim they don't, others claim that all do, see Chris Kresser's article
Often contain guar gum which can be irritating to some guts
Some don't tolerate it well

Heavy Whipping Cream PROS:
Contains good amounts of vitamins, esp. A and D if from pastured cows
May be less processed than canned coconut milk
Can be obtained locally (for most people)
Generally nutritious
Good fatty acid profile

Heavy Whipping Cream CONS:
Not tolerated by some (lactose, casein, and other compounds can be problematic for some)
Insulin and growth promoting (this may be a pro for some, and it's much less so than milk)
May contain things you don't want, depending on how the cows are treated (e.g. hormones)

I think they both have goods and bads, depending on the individual and their needs. If you can tolerate it, I think the extra vitamins in cream and the reduced exposure to BPA pushes in favor of cream. You can buy boxes of coconut milk from Aroy-D that are supposed to be BPA free, though. I ordered a case and they're tasty. It's also possible to make it from coconuts directly, which would potentially make it a less processed food product than cream (depending on how you figure it).

I guess my takeaway is that both have their place. So go with what tastes good and makes you feel good!

FYI re dairy Although Health Canada does not permit the use of recombinant bovine somatotropin (rbST), this growth hormone is legal and considered safe in the U.S. and other countries.

Not sure what the status of other countries other than the US is. I am Canadian. no growth hormones in our dairy.

I use both whipping cream (35%) and just found some good coconut milk. "Asian" brand, I use whipping cream for my sweet /desert tooth. whipped with a drop of stevia and some organic vanilla and frozen raspberries now and then. or mix it with cream cheese.

As far as preference, cream wins over coconut any day. I don't know what the deal is, but coconut cream just doesn't seem to bond with the coffee in the same way that cream does. My coffee still tastes runny and thin with coconut.

I'm actually on tea right now (adrenal fatigue protocols...) and I tried adding a pat of butter today and coconut cream. Still no dice. I even bought one of those frother devices...no dice.

You mentioned you enjoy both, so I say whatever floats your boat. :)

Anecdotally speaking, I tried using equal amounts (calorie-wise) of one and then the other, and discovered I had a hard time losing/maintaining weight on heavy cream. I drink my Americanos with coconut oil, or grassy butter once in a great while. I know others have had the opposite experience, my advice is try each for a few weeks and see how it goes for you.

Have you tried "bullet proof" coffee? Just stick your coffee in a blender with coconut oil, butter or both and whip till its well distributed. It makes it super creamy without the issues inherent in canned coconut milk or cream.