I do not know any of these things for sure, but they are my opinion. I decided on getting a quality flute made of cocobolo instead of blackwood for the following reasons:
(1) Flutes are big investments and no place for experimenting. Therefore in think blackwood is used because of tradition. The west coast of Mexico was not part of the British Empire and cocobolo was not well known. It only grows on the west coast of Mexico and Central America.
(2) If you want a highly stable wood, go to the pool hall and see what the guys that make big money make queue sticks out of–cocobolo.
(3) Cocobolo seems (and of this I am not sure) more oily and water repellent. Jon or Johnny Gallagher will tell you that it is actually “waxy” when turning on the lath.
(4) Allergy should not be a consideration of wood choice because a ring of super-glue should be standard around the embouchure of any of the rosewood family, including blackwood, cacaos, cocobolo, or other rosewood family. The super-glue chemically reacts with the wood to put a thin glassy surface that feels much better to the lips than any wood surface and isolates from the toxins. Super-glue actually turns a thin layer of wood into polymer.
(5) It is gorgeous.
The player still has to handle the flute and finger it.
If he / she is allergic to the wood it is made of that may pose a problem unless you cover the flute with superglue.
I still do not understand why the end of the grain is not protected with superglue against the entry of moisture .
Nelson,
Please post a picture of your new cocobolo flute. It sounds lovely! How does it play?
Thanks, Jeanie
I’ll post my flute on the porn page when I work out how to do pictures. The sound is not the loudest, but easy to make, especially the high notes. I do a good bit of vocal accompanying and it is perfect for that. It was exposed to ammonia vapors to give it a chocolate/brown look with a hint of the grain. There is a sheath covering the bottom of the silver slid with subtle calibration rings and the silver of the slide is not exposed.
To answer Andrew’s concern about allergy problems with handling. Loran said that she and many others she has been evolved with in her endeavors with recorder and flute making with a large firm, handling has never been a problem. Also, I have never heard of pool sharks having problems, so says the cocobolo dealer in Florida. Had I not been assured to that extent, I would never have chosen cocobolo. I could be wrong, though.
Also, when I first got my flute, I played it a couple hours a day straight off, I’m not very bright, being a West Virginia hillbilly. There was no evidence of swelling or shrinking from the moisture. I always take it apart after playing. I had never had a flute or bagpipe with tenons wrapped in silk thread before, I like it. It goes on smooth and is springy. Of course most of you probably know this. By the way, the first time cocobolo got my attention was when I saw a Highland bagpipe chanter made from it. They are slim-walled, small and actually flexible. I would not have a GHB chanter made of anything but Delran with the rough treatment and weather exposure of these pipes. E.g. at funerals on rainy days, everybody stands under the canapé (except the one getting berried, they do not stand), but I have to go up on the hill and pipe. If I were one of those guys that marches in front of soldiers (in the rain), in order to get shot, I would definitely us a Delran chanter. GHB chanters are the only woodwinds that, according to the physics, could sound a difference in wall materials. The sound is about 10 times as loud, the bore is 1/10 the area and the walls are thin. The wall vibration for flutes walls changes the sound amplitude about 1 part in 10,000. With a chanter, I would guess it would be about 1 part in 1000 or even more. This is enough to, maybe, hear the difference. I wouldn’t care the difference if I had to fall down in the mud dead. Sorry to ramble off topic.
I’ve now spent a fair amount of playing both these flutes pretty hard, and here’s where I net out:
My blackwood McGee Pratten outhonks my cocus Hammy.
My cocus Hammy outbarks my McGee Pratten.
The Hammy can give you a slightly hoarse, raspy, reedy sound that cuts thru the air like a shot of firewater thru a chest cold. The McGee booms like a foghorn (more Olwellian, IMO).
The Hamilton (as well as my Murray) sounds quintessentially Irish, at least as I hear it. The McGee … eh, not so much, but you can put enough bark on it that it’ll go fine. And it’s so big-hearted and honest and rich-sounding it’s addicting.
Two totally different tone characters, two totally different flutes to play, but both of them REAL loud when they wanna be. 
And yes, bummer, I have to superglue the Hammy anymore – I seem to be developing an allergy. 
But dang, that cocus is gorgeous.
That’s a great description, Cathy, about honking and barking, and how that compares to the foghorn effect. I’ve been wondering about the foghorn type tone, since it doesn’t seem to appeal to me. The Hammy would probably suit me more than an Olwell or McGee, in the models you are speaking of. Of course, that’s on an academic level, and getting a chance to play either in person might blow that theory in a hurry!
Thanks for that bit of insight, anyway!
Our own Jon C. has recently developed an allergic reaction to cocobolo, which is too bad since a lot of his flutes are made of cocobolo…I think he’s going to start focusing on blackwood now.