Tannoy cheviot vs Arden what should I expect from each?

The midrange is the hardest thing in any speaker. Too small and your trying to cover it with a tweeter, too big and you have a bass driver muddling along. 
I would have to hear them before buying. They have such a big following but that means nothing in audio if you don't fall into that group.

I have been given the OK by the boss to buy my last set of speakers and will buy Tannoy. I’m looking at the Cheviots, Ardens and the Turnberrys as well. I will also audition them as soon as I can get a free day. I’m lucky that Upscale Audio is only 35 miles away and down 1 freeway (210 east) at that.

At the moment, I’m leaning toward the Turnberry’s which is funny because the last time I was there, I saw the (Tannoy) prestige line near the entrance and thought...’who buys this nutty stuff’? But the closer you look, the more appeal there seams to be...for me.

I have owned the Tannoy Ardens for 44 years and was fortunate to be able to audition the entire Legacy group (then four sizes) in person in a controlled room in '77. I wavered between them only because the Ardens are really BIG, but I finally went with them because the enclosure size DOES make a difference in rich, full bass response and a distinct imaging...so hard to convey what you hear but I have never heard a sweeter speaker. It is not heavy on treble so remember that when picking you amplification, but I use mine with tubes and LOVE the warmth and smoothness. Never been tempted by another..likely never will. I was lucky to find my "forever" speakers at the age of 25! I'm now in a custody battle as when we divorced we agreed to switch back and forth every five years..now he is trying to keep them but I am ready to hear them again! You will never regret getting them!

This bring tear to my eye but me my advices to look for more speed the thunder. Solid state rock you world. Look at size and girth of big Maggie speaker.  This give you speed and depth you longing to for without be frail and fragile. Maybe this get you over hump and give you balance away from past speaker. You get big excite experience again and forget about forever.  You might like explore sub too like I have in gym.

On the comments about speaker sizes and frequency coverage. I currently have Salk Songtowers and they have a small tweeter (3/4") that crossed over lower than most 1" domes.  The response from these speakers is surprisingly smooth. Two 5" mid-woofers in a transmission line cabinet in the right room can rattle the walls. I was frankly shocked.
They're in a decent (acoustically speaking) room so that certainly helps.

Well-matched drivers and crossovers will challenge convention.