I've used the Thumb Rest for close to 3 years now... it hasn't left a mark at all! In fact it protected my flute from getting the usual wear in the area wear the thumb is placed.

<Added>

Sorry I meant to spell the second wear as - Where!

I agree with Suzie. Those Bo-pep things are rock hard and not comfortable at all. A Bo-pep came on a used flute that I had one time and I tried it out on my flute and it scratched it all up. Luckily for me, I have a buffing machine and buffed it right out. I really think that you will like the velcro idea Jose. I have used one on my left hand for years and really like it. I have tried some of the other gadgets that are offered on the market and didn't like them. They felt so foreign on my flute and hindered my finger reach.

I have one, I got it at my local music store. I don't really have an opinion though. Its ok but for me it did not do that much.

That guy's crazy! His flute might be an 'innovation' but it's a bit of an eyesore! It'll never replace the Boehm system, but maybe one day, something will!
I like to go natural on my instruments. Attachments I find, come back to haunt you! Eg. You have an attachment for years, you rely on it, then when you want to play fast passages, you can't! You've learnt to play with the attachment, then when you don't want it, you struggle to play without it!
Of course, this is different to just a bit of material stuck on to cushion it. I mean things like Thumbports, Finger rests/saddles...
It'll probably hinder, not help!
Still, that's just my opinion! If you like it, I can't tell you not to like it!
Pyface

Pyface,

The future flute could also look like this, this is Taiwanese new Ceramic Metal (they call it plastic steel) flute, very tough, easy to make, very light, and futuristic:
http://i927.photobucket.com/albums/ad112/pyrioni15/g31.jpg
http://i927.photobucket.com/albums/ad112/pyrioni15/nanopad.jpg

Lots of discrepancy! Nice to see so much feedback.

Yes, I will not risk unless I am convinced it could really help without harming my technique and the flute integrity. The Velcro (or similar) solution is easy to test and will show the way to follow.

Thank you all.

yes suzie,

Cermet flute was out many years ago already, one of my ex-ex-teacher was from Taiwan, she studied flute in Paris, her good friend is a Paris headjoint maker and also Taiwan Guo's music flute maker and headjoint maker
http://www.flute.com.tw/
She introduced me to Mr.Guo, and Mr.Guo let me test his Cermet Headjoint years ago, it's an awesome headjoint, but I find that Cermet head sounded too dry, too crispy, or even Thin toned, similar to my bamboo headjoint. Not to my taste, so I never bought one.
(sorry Mr.Guo, it's just my taste problem, great headjoint tho)
here is someone test-played it
http://www.youtube.com/watch?v=cbrvubf7sgQ (2:30)

I love those flutes! Suz and I played on some at the flute fair a couple years ago. Suzie sounded better on it than me because her style of playing matched the sound better in my opinion. She is able to play a lot of Celtic/Irish stuff off the top of her head. The sound was very thin to me, but different. I just loved them because they were so LIGHT and comfy to play! The headjoints are fun to mess with too. I wouldn't play one as my main headjoint, but on the side for different style of playing, they would be fun.
Suz, what was the brand of the wood headjoint that we both liked a lot at the flute fair? I can't remember.
Okay, sorry, getting off topic. I just love to talk about headjoint and flute constructions