I have T5P 2nd gen for about a month. Using directly from Ibasso DX50. After about 40 hours of listening at home, in bus and subway (tube) I am satisfied. I used Beyer Momentum for 2 years before. I use the new ones mostly on the go, sometimes at home. Here are my first impressions:
1.) very well made, good materials, such as Momentums. The same package, only bigger,
2.) they are about 75% heavier and bigger to Momentums, so when I am walking it´s kind a shaking on my head (ears), It´s only an impression, the earspads are sitting on the place, but the gravitation works, so I have to improve the clamp force - specialy the upper half of the earcups. I am still not sure how, but I am convinced it will work for me. You know everybody has a different headshape,
3.) as I would say, the isolation is the same as Momentums - you can hear the environment a bit, but it is good for your orientation in different situations in town or in vehicle.
4.) Is there any sound leakage? I don´t know. Sometimes I´m hearing on moderate level, but still no one turned a head to me, no one cares, even if the bus is crowded for example.
5.) On the street, in bus or anywhere no one cares what I am wearing on my head. A lot of people in town are listening to music by headphones (smaller though).
6.) T5P is more comfortable on the head to Momentums. The earpads lay around ears, in case of Momentums partly on the ears.
7.) Momentums (first gen.) are to bassy for me, I had to set equalizer -1 to -2 decib and +1 for heights. On the other hand T5P has everything on its place. Incredible heights (Momentums plays height a bit down, in traffic OK but on calm places it´s just not good. The T5P has very nice and tight bass, but it is fading away sometimes in traffic and than the music seems to be unbalanced. The drums specially get sometimes anoying. I am still getting used to the sound of T5P.
8.) The details and the soundstage is incomparable to Momentums. The Momentums are something far far away from T5P. T5P excels!
9.) I found specially the sound of the guitars (I hear mostly rock and metal) so nice! Specially the sound of the Red special (Brian May, e.g. song "Back chat") or Strat of Jimi Hendrix is soooo incredible (album "Electric ladyland")! The whole album "Themes" by Silent stream of godless elegy is fantastic! It excels on high quality recording, but low quality is still OK. Momentums has no sparkling, tha bass blurs to mids, the sound is more compact but not fun. T5P are more challenging for listening - I don´t know how to describe it correctly. For short you have to have a good mood, no stress and no headache. Than you will have a lot of enjoying time with these!
10.) T5P has better punch to Momentums.
So that´s all for now