Reference with Hifi/end Castle Howard S3 speakears

[imol]

Hi,
so newbie in here. with all due respect:
I'm just trying to start a small mastering facility. Nothing extravagant. Budget is limited plus gear in my country is twice the average price as in the US or Europe.

I was wondering if some HiFi/HiEnd floorstander speakers would be of a descent reference for listening and doing my job.
At the time I have listened to a rare pair of Castle Howard S3 speakers (3000 Us $) and a rare pair of Sony SS X90ED ones(1900 Us $). I have also tested Proac's Studio 125 and B&W's 683 for 2700 us $ (did not like this pair so much thou). They all sound fair to me, but I was just wondering If any of them would be of a good starting point as a full range reference for mastering.
Any help will be much appreciated.
Any hint? a different approach to the project...maybe some pro speakers which could also do the job not necessary being part of the hifi hi end family?

thanks!