Romi charged me about 1K USD and they took over a week to do it as they were studying the components and playing with it. Future mods can be done within a few days now they have the know how. Now with the the pandemic, I’m not sure if they can work on offering a better price or not, but it’s worth asking. Check in this forum for Romi mods. I found out about them via this forum and have read that many customers have sent in their units to be modded and are very happy with it. I was a bit skeptical at first, before and after the mod of the P6 due to minor sound changes. But as I am replying to you right now and listening to the P6, I have no regrets at all. Just a big smile on my face.
I am fully satisfied with the current sound quality of stock player but then we always go for any tangible improvement if feasible.
I have a different story than yours as you were requiring more power but I actually want to bring down volume level to -10db so I can enjoy ultra
low listening volume on IEMs. I do not feel comfortable that even at lowest volume it's loud for bed time listening. I have already sent them an email
so let's see what they can offer. Honestly, I really don't feel I need the mod but who knows...