Ascend Astarion or not???

I’ve seen sooo many conflicting opinions on this one. I’m doing a resist dark urge run but was planning to ascend him.. apparently this is not the best choice for him tho? I’ve seen a lot of people say it’s better to let him stay a spawn, and that the spawn ending is actually his happy ending. I’m playing my first and second playthrough simultaneously but my second (durge) is further behind. So I haven’t actually seen the end yet on my first (I’m in act 3) and haven’t seen how the ascension plays out. I don’t mind spoilers, pls help!

Edit: forgot to add I’m romancing him on Durge run!