I wish it was easier to find chicken and pork that was raised outdoors without grain more often. They have excellent sources of D.
I don't find it unpleasant; have got used to that 
I tried the cinnamon flavor, and that burned a lot. I think the other one I tried was orange. Well, whatever it was, it wasn't so "burny".
... It does say on the bottle not to take it if you are allergic to sea food and although I have had allergic reactions to shrimps and mussels, I eat fish regularly without problems.
My son started bleeding recently internally after eating fish (after long time strict veg no eggs ever either), that caused some really bad anemia for a few days. He recovered from that but his stomach is still not as good as before that incident. We're not sure if it was eating the fish that got him to hemmorage, or some combo or a fragment of some kind or something else. We know others who got problems like that from fish but they are doing fine afterward on raw land meat. He has shown possible signs of sensitivity to some type of shellfish in the distant past. He hasn't tried CLO (or land meat), but is using a dry vitamin D2 from the healthfood store. At least we know now he too may get this throat burning when he tries CLO, and we won't think it's rare that it happens etc.