Interestingly, the specs of the datacenter they are allegedly hosted match with an existing Estonian datacenter: Levira Cloud.
It is a DC hosted in a radio tower. A rather interesting concept: radio towers are built to last, and especially since the change from analogue to digital sending equipment they have excess power capacity and excess space. These towers supplement their income by turning floors into datacenters, and are able to offer high density with little effort. They're doing that everywhere in Europe ATM, and I really have to say: I love it.
The gensets and UPS could perhaps even match the specified capacity.
The cooling specs are a bit odd, this tower should have no problems using free cooling. And I don't see these raised floors. In fact, the pictures look like a pre-2008 DC. But these are problems of the DC, not of HashFlare..
In short, if they're a scam, the specs of the datacenters do not give ammunition to proof it.
EDIT: link to the hosting DC: http://www.leviracloud.eu/