Re: Can anything compete with the RAAL tower or Sierra 2?
The Elac speakers are not going to be as accurate. They have an accentuated sound in the bass range, and it's more of a sweet sound rather than completely accurate. Good speakers, just not the same kind of design intent as the Sierra 2 or Tower.
From what I've heard of the KEF LS50, it's also a great sounding speaker, but may not be the most accurate. It apparently images very well, so may be slightly better than the Sierra 2, but I don't know. I did read a shootout a guy did between the LS50 and the Sierra 2 and I believe he ended up keeping the LS50, regretting it, and then buying the Sierra 2 again. It's just a matter of taste in the end, both incredible speakers, but one may provide a better experience for each person for a different reason (accuracy, soundstage, imagine, bass impact, instrument separation, etc...). Since you asked specifically about clear and open speakers, I really doubt you'll find anything better for $1500. You're probably talking $5000+ for something more clear and open. I don't know of any other speaker company with less smoothing on their frequency response charts, or of anyone that sells such an incredible tweeter for such a low price.
If I were you I would invest that money in better/more subwoofers, better/bigger amplification, room correction or DSP.
-Alex
PS4/Nvidia Shield --> Emotiva XMC-1 --> Emotiva XPA-5 --> Ascend Acoustics Sierra Towers and Horizon Center w/ RAAL tweeters (L/C/R), HTM-200 SE (Surrounds), 2x Rythmik F12 subwoofers