First off, I have both a Behringer USB interface and the Tascam us1641.
First thing you'll have to do is completely remove all traces of asio4all from your system.
You don't need it and it will mess everything up.
The us1641 - install the latest drivers from the website. They released the last update in Dec 2014 and for me they have been rock solid. Driver V 2.05
http://tascam.com/product/us-1641/downloads/ Open Sonar and set to ASIO mode and you will now have all 16 input and 4 outputs.
The Tascam is a good interface with only one small downside that being not the greatest round trip latency performance. But this is the same with most interfaces under $300. Just use the direct monitoring and all will be perfectly fine.
The Behginger USB- uses "USB audio codex" which can be set in WDM mode in Sonar.
asio4all is also a WDM driver, it is not ASIO. So you don't need asio4all, you have a driver already.
The Behringer is fine for audio playback and one pass stereo recordings. It will not work for multi track recording. The overdub tracks will end up out of sync to others. This is common to WDM mode. So use the Tascam for all work in Sonar.