I recently bought the Ditanium mouthpiece to use on my og glass TM-stems.
Didn't buy it for the cooling but wanted something tapered and somewhat smaller diameter then the glass stem just for the mouthfeel. I'm mostly using the OG glass stem and always felt that the large diameter wasn't 100% comfortable for me.
So that was the main reason for buying it but i have to say that i was amazed by the added cooling it provides: Not just from the added length and the 'cool touch' of the metal but it feels like it actually absorbs quite some heat from the vapor too. I can take pretty huge hits before it starts heating up. On the short glass it's exactly the same size as the long glass stem but it really hit much smoother imo. Mainly been using it on the long stem tho, really excellent cooling and i love the look ant the feel of it!
I was an instant fan and i ordered a second one after trying it once!
Somehow makes drawing easier and more comfortable and i just love the mouthfeel and the shape of it: it turns the glass stem into a steampunk cigar!
Be advised: it doesn't come with o-rings and the TM ones don't really fit. I managed to make some with some silicone whip i had lying around but i also read that the crafty o-rings (?) should be the right size...
Ordered at docteur vaporisateur btw.
Edited to add a picture of it on the shorty stem: