I once tried making marmalade with fresh Satsuma Mandarin oranges and found that they are very mild and sweet—even the peel is milder than most other oranges. It makes for a rather bland marmalade and I suspect you’d have the same trouble with orange curd. Not to mention the difficulties in squeezing all those tiny oranges! I’d say go with regular orange curd, too. Maybe you can get some mandarin orange flavored liqueur or essence to add? And garnish with mandarin orange segments?
P.S. I also made home-canned Mandarin orange segments in syrup, and candied some of the peel. Those were both very successful although a lot of work. The peel came out very soft, flexible, and not bitter—again, milder tasting than other orange peels, but lovely for eating just plain!