Pretty but not ready for prime time
When using the Gauge web parts to connect to an Excel Workbook in an Excel trusted location we received SOAP errors regarding Maximum concurrent connections. This behavior did not occur when the web part was first configured on a page, but occurred if the page was refreshed. It sometimes worked for multiple refreshes of the page for some users – but eventually gave the SOAP error.
Navigating away from the page in the browser and reopening it did not change the behavior.
Closing the browser and reopening it to the page with the gauge web parts did not change the behavior.
We did not receive this error when only using Excel Web Access web parts connecting to the same location on the same page of the same site.
The error occurred more rapidly if there are multiple gauges in the site pointing to the same Excel trusted location.
We raised the limit for concurrent user connections in this trusted location from 5 (default) to 10 and were able to load the page and web parts fine one to three more times. Then we received the error again.
We tried reducing the idle session timeout setting for both the user sessions and the Excel Calculation sessions, but this did not seem to have any effect on the behavior.
We also found some of the gauges did not render properly when installed in a 64-bit environment.
When we contacted Dundas support, they confirmed the behavior and reluctantly verified our findings that there were two connections being created for each chart on a rendered page.
Also, we found that the connections would be refreshed on a page refresh along with two new ones being created. So, if a page with two charts was loaded that is 4 connections. If that page was refreshed once before the connections timed out, there would now be 8 connections. If ten users each hit the page in the same interval, that would be 20 connections with virtually unlimited scaling if they refreshed the page.
We decided to hold off on our purchase.