I've got a Leblanc Dynamique, and I'm quite happy with it. I've played several Selmer Centered Tones one Balanced Tone, a Leblanc Dynamic and a Dynamic H, before I finally settled that my current clarinet is what I really love to play on (even with the slight banding and tiny chip in a tenon). That being said I'm pretty sure (and anyone feel free to correct me) that any of these horns I've mentioned all utilize what classifies as a large bore.
I had tried out the Center Tones from a gentleman I was studying with at the time, the Balanced Tone from a friend, and the Dynamics/Dynamique were from everyone's favourite (insert sarcasm here) ebay. Be warned, buying from ebay, you MUST be informed and ask lots of questions, especially due to the fact that these are vintage instruments and may have serious problems (my Dynamique, one band, and a filled chip)... Ask as many questions as possible, and if the seller pushes back or is unresponsive dump'em.
I am unsure what current professional/intermediate grade large bore clarinets bring to the table, but I like how mine sounds and plays for a total investment of about 350 bucks, and will be holding on to it for a long long time to come!
Why are you looking for a large bore cl, if I may ask? What style playing are you looking to do with it, or is it that you're interested in the difference in response?