Hope all is well.

I need some of that tube wisdom!

Got a really nice pair of "audiophile" great headphones as a little treat for myself :

https://en-ca.sennheiser.com/high-quality-headphones-around-ear-audio-surround-hd-650

And yes i got them on sale, plus i financed them .... I know

Now like usual, I've over-graded and now need to play catch up with the rest of my gear.

The HD650 are 300OHm, so I need something to drive them.

Everything I've read leans towards the synergy created with a tube amp. ( I've been watching the snake oil)

I have narrowed down my choices to a few, I just wanted your opinion.

My first choice right now is the DARKVOICE 336SE OTL; it has great reviews and pairs very well with the HD650's. It uses some cool tubes I've never heard of as well, only down side, is it's unbalanced both input and output (thats the new thing, balanced headphones outs via XLR) and may get way too hot if i'm using it for gaming/youtube/general media.

https://drop.com/buy/dark-voice-366se/reviews?sort=endorsements#reviews

Second choice is the Little dot MK 2. Same idea, but this one uses 4 tubes, CV4010? Same issues with basic IO options...I'll be coming in from a studio quality DAC (digital audio convertor) at balanced XLR , so I may need something to properly bring the signal level down to RCA without mucking it up.

https://drop.com/buy/little-dot-mkii-tube-headphone-amp

My least choice for OTL is the XDUOO TA-20 , which ticks all the balanced boxes; has XLR input, and XLR out for the newer style headphones. But I feel like this unit does too much, and therefore loses build quality having so many features. Its tube section is just two 12au7s, and I feel like its almost just for looks, not for audio "color"

https://drop.com/buy/xduoo-ta-20-balanced-headphone-amp/talk#discussions

Finally we have the Topping A90, which is a SS amp, based on the THX AAA system, that has zero color and is ment to fully reproduce audio the way the designer meant for it to be, not a paid advertisement hahaha. To be honest this is the amp I really wanted to begin with, but I've been led into the direction of tubes for the case of the HD 650. It's a pretty penny, 500 USD, for a headphone amp, but it does everything I want! XLR in and out, plus I can use it as a preamp down the road, and output VIA RCA into a tube amp, which I feel is the better way to route the audio into the tube amp instead of some janky XLR to RCA cable.

Hope all is well, sorry ear full.

Any thoughts