I don't use that bean but you should know that supply of Sumatrans (and Java) remain quite tight for at least another 3+ months, e.g. demand still exceeds supply.
The closest I have is a Java FairTrade Organic Ujangjaya (ASKOGO) which is a very nice bean.
Next week I am getting one of the sweetest and cleanest Sumatran's tasted in years - it's simply called RFA Mandheling GR1
My suggestion is to also look at Kuda Mas - a stunning bean in every respect and in my humble, personal opinion superior to the Kalistat - but it all comes down to how and what you are using the bean for.