Anyone listen to Zu Audio's Definition Mk3?

Ghostinthemachine, I can't comment on your experience since I'm not connected with Zu or their distributors, but if you haven't already bought alternative speakers do contact Sean at Zu and see what he can do. I believe they have run 60 day risk free home trials for many of their speakers in the past, and maybe this could be arranged for the Def4s.
It's a shame, since you're missing out on one of the most holistic experiences in music reproduction, which I am buying further into myself personally by purchasing the Def4s. Ironically enough, since you're not considering, I complete the transaction today.

I echo what Spirit says. While I have no experience with Zu's Canadian distributor, I have had years of experience with Sean and the rest of Zu; and they are a total class act. I first bought Def1.5s using the 60 day home trial period and have since upgraded to the Def2s and now the Def4s. Like you, I wanted to hear Zu speakers in a store first. However, the converse is that hearing speakers in a store does not tell you how they will sound at home. (I have certainly had the latter experience.) If you want to contact Zu, the best way is through their website: www.zuaudio.com

There are few dealers since Zu prefers to sell direct. However, one dealer "relatively" close to Toronto is near Buffalo:

AudioFeil International
9405 Meriul Lane
Clarence Center, NY 14032
USA
716-400-6177

Bill Feil (the proprietor of Audiofeil) was very helpful when I bought my first pair of Zu Defs. However, you need to call him in advance. Good Luck.