I have used one and its not practical for long term use under stress. The handle is just not user friendly. They are high on the neat factor however.
And by not practical are we talking about actual breakage or malfunction of some kind or is it just your preference.
If its the former, then I have a feeling that its a freak accident as its would be the first time I've ever heard of a hollow handled reeve breaking. If its the latter then, while you are certianly entitled to your preference, that and .02 will get you a cup of coffee.
Reeve hollow handle knives are high quality field pieces. No doubt people have their preferences. Some people prefer certian brands over others. That, however, doesn't mean that these brands are crap.
If someone was stuck in the middle of nowhere with a reeve, they could do a whole hell of alot worse. And that ignores anything that might be stored in the handle.