Thanks to noobandroid, Chodi and SunTanScanMan for your useful comments. I think that I'll hold off on the T1 until I have a balanced setup, which may be quite a while. I have invested a lot in single-ended. On the other hand, temptation is a terrible thing.
noobandroid - I have posted a lot on the Q701s - I'll find one of my summaries of my findings and I'll PM you so as not to derail this thread.