Meiatflask, to answer part of your question, while I have not directly compared the Proacs to the Decapos I expect that if may be a matter of preference. I generally stay away from recommending one thing over another but suffice to say I much prefer the Ref 3a presentation.
DEFINITELY the beryllium tweeter over the soft dome. I do agree that in a showroom they can sound a bit bright but assuredly when fully broken in there really is no comparison. The extension and added air can sound most lifelike, present and transparent, no stridency or brightness whatsoever. A listener acclimated to the soft dome may not be won over but I feel quite adamant about the BE. Tash wouldn't use it if it wasn't better. It might be better to get opinions of those with a pair properly broken in rather than brief listens. My initial response was a bit of brightness as well. I've had experienced listeners comment repeatly. Unfortunately it does take some hours for them to settle in.
DEFINITELY the beryllium tweeter over the soft dome. I do agree that in a showroom they can sound a bit bright but assuredly when fully broken in there really is no comparison. The extension and added air can sound most lifelike, present and transparent, no stridency or brightness whatsoever. A listener acclimated to the soft dome may not be won over but I feel quite adamant about the BE. Tash wouldn't use it if it wasn't better. It might be better to get opinions of those with a pair properly broken in rather than brief listens. My initial response was a bit of brightness as well. I've had experienced listeners comment repeatly. Unfortunately it does take some hours for them to settle in.