Nothing very specific, but addressing his question: he basically asked: "if both are comparable technically, I should those whose described sound sig I prefer, right?" I think there are other things to consider in that case.
For example, I find acrylic slightly faster to put on and take off than Silicone, so if you need to pop them in and out often, having only a silicone ciem is not ideal. Unless you also have universals. Besides, if you are someone who does does NOT take good care of his stuff, silicone ciems are slightly more fragile. Then, if you have sensitive canals, I find silicone much less aggressive than acrylic. If you live in a very hot / humid place, some people find silicone is not optimal when you swet a lot. I was thinking about such things. And there might be other things.
And there are other factors known to all between these two products: what is your source (as they have VERY different impedance), where do you live (regarding Spiral Ears and deliverely outside Europe), price (SE5 is 1.5 times the price of Miracles), etc.
I used to think silicone is more durable than acrylic but I guess I am wrong. Maybe acrylic shells filled with silicone are very durable so I misremember.
I found your explanation very nice and incredibly useful. I have to say, it will be my first ciem and I won't have money to buy second one for a long time. Maybe acrylic could be a better idea as a starter for me. Also day to day use differences like easy to put in take out can be important. I also don't know how is the shape of my ear canal, is it gonna be easy to get a ciem or the canal is rather sensitive. We will see I guess.
I am currently in Belgium for my master and even after my master I am planning to stay here. I guess it is not the killing weather for customs but is it the ideal? I don't know honestly. I am someone who takes care of his purchases and baby them so I hope I won't get problem with the durability of the ciems.
Money is another concern. Miracles are around 750 euro in here and SE5 way is 1250 euros I guess. I am also interested in Hidition NT6 pro which is around 950 euros. The truth is, I also need a DAP to pair with my high end ciem and only if I buy Miracles I have enough for HDP R10 otherwise HDP R10 has to come a few months later than my ciems.
I must thank all of you for all the responses, answers and helps. Today I finished my last exam then I have a little holiday. When I come back I will decide what to order and the process will be started.