I am new at the meringue butter creams, so I'm wondering which you all prefer (and why, if you want to leave a comment after you vote).

Thanks for sharing!

They are the same, just a different way to get to the final product. And that's why I would rather make IMBC. I'd rather boil sugar to pour on my eggs than stir eggs and sugar on a double boiler. I did that twice and then made my choice to go for the IMBC. I haven't made any other frosting, though and maybe I should try the others at least once!

Ditto. They are the same -- just a different approach. I am in the opposite camp and like dissolving the sugar in the egg whites. No reason, I suppose, except that I learned that method first and it has always worked for me.

I tried both IMBC and SMBC a few times, and prefer making SMBC since it is easier to make (IMHO)and works everytime. I had a little less control over pouring the boiling syrup in egg whites.
I'd say try both and see which one is easier for you to make.

FRENCH!!!!
I prefer my version of a "French Buttercream" using the whole egg; or the classic "French Mousseline Buttercream", where you make a traditional French Buttercream with all yolks (same method as IMBC) and then fold in Italian Meringue (Not IMBC).
French buttercreams (or any variation of this type of BC that contains yolks) IMO have more of a depth, richness and well rounded flavor than you can get from just the whites.
Now please understand I LOOOOVE them all and can eat them with a spoon for breakfast lunch, dinner and snacks!
But I love FBC more
Now for my die hard European buttercream fans, I do a version of a "French" buttercream that basically uses the whole egg.
For those people who don't care for the whole "buttery" taste I do the French Mousseline BC. Adding a little Italian Meringue (minus the butter) lightens up that buttery taste that some people dislike, but keeps a similar consistency, and mouth feel.
I do IMBC if I need white BC because I use a lot of Italian meringue in my FBC and its easy just to add butter.
I make SMBC if I want to make a Caramel BC by just using brown sugar, because it's easy.
Wow, I guess I'm all over the place now that I think about it!
All in all, I must say my #1 go to is my FBC!
HTH!
Sorry so long!

(editing typos: Gosh I can't spell sometimes )

Do you mind sharing your recipes for Traditional FBC and Mousseline FB?

Thanks in advance...