I've done a lot of thread research on viable hybrids. Also, many of you have responded to threads I've started -which has been extremely helpful. It seems that Varicor Excel and Pirastro Flatchome Steel are the only hybrid candidates free of significant compromises or shortcomings. The next in line is the Corelli series (370 or 380). Corellis seem to have one drawback, namely that that G string is too darn thin. I ended up making a decision based on cost and buying an E and an A 380 TX from Southwest Strings. I love the way these things bow. I started playing some arco studies and I could negotiate passages that I couldn't with the Helicores. I know that I could progress with my arco a lot faster with these and that's worth a lot. But the E is a little dark and thuddy for jazz. Is the tungsten E (370) any brighter? Corellis are so atypical that that don't mix and match to well with other strings. You have to go with the complete set. If the 370 has a brighter sound I think that combination would be perfect for me.