However, all three came to the same conclusions about me. You have to decide what means the most to you. If price is critical, examine the costs closely, and estimate how many tests you think you will administer. If quality of the report is important, ask to see a copy of a sample report from each company. They should send you one gratis.
Support is a critical feature for any software.
The IVA and TOVA are the only products of the companies that distribute them. The Conners is distributed by MHS which publishes numerous assessment measures. As such, the IVA and TOVA support is more personal. IVA support, for example, is provided by either the test developer or his wife. TOVA support staff are equally personable and responsive.