HOLOGIC was recognized as one of the top three mammography providers in the 2012 KLAS Medical Equipment Vendor of the Year Awards, and the KLAS market research report states that "HOLOGIC has become the market leader in the breast imaging market with its new technology of Digital Breast Tomosynthesis".
Their medical equipment should be fine! If you want to buy it, you can go to the hospitals that have introduced their devices to see and hear how the reputation, but also to do a market research and then go to make a decision. This can only provide you with some information, the specific has to be combined with the actual situation!