What I don't like about the adapters is that they always seem to stick out in the worst places on stage and are real easy to run into.
My JBL speakers have Speakon and 1/4" jacks, I don't see what the problem is and why more companies don't do that. I've thought about adding 1/4" jacks to a Behringer pa I have that only has Speakon. What's nice about 1/4" plugs is that you can use a right angle one and put your amp right against the wall.