I have been playing ITM for over 30 years. My instruments are wooden flute (I have an 1882 8-key, an 1850 William Hall & Son Siccama-style 10-key, a 1921 fully keyed Radcliff and two Casey Burns flutes), whistle, bodhran, and bones.
I also play silver Boehm flute (over 40 years).
I bought the Siccama (10 keys) and Radcliff flutes to manage around some loss of sensitivity in my finger tips (peripheral neuropathy - no cure or treatment). Not having to seal open holes more or less solves the problem. Having a key over G and D (Siccama) got me about 90% there, but my Radcliff in 2016 totally nails it. Wonderful instrument. Both flutes are thankfully A=440.