I have a few Hush jumpers. Their linen/cotton/summery ones have been great quality wise. A wool one pretty good - has bobbled a bit but it is now 3 years old and still OK. Got some bamboo ones - shocking - thin and baggy after the first or second wash.
I find their t-shirts AWFUL.
I would be wary to be honest - only because it can be hit or miss and it is such a lot of money.
Maybe see if you get more responses from here and/or reviews of their cashmere before you buy.
Have you looked at Uniqlo - I have a v-neck cashmere jumper from there which has been great. Possibly not as fine a knit as the Hush one though.