Well Hiker, I have taken the plunge and ordered a matched quad of winged Cs so thanks for the benefit of your experience. I'll report back in due course and let you know how they behaved in my particular set up. If anyone else has contributions to make to this thread then please don't consider it closed. This Glowmaster amp is a 'keeper' so I'll be interested in any tweaks, which you feel wring the most out of your unit. I have replaced the stock power cable with a Zu Bok which made a significant improvement and I have ordered some LSU No Spikes (I believe they are called "Spike Sound Will" on the other side of the pond) to evaluate for isolation purposes as the amp is too heavy for both my SAP Relaxa and Seismic Sink.
Of course, any alternative tube combinations i'd be fascinated to hear about...
Of course, any alternative tube combinations i'd be fascinated to hear about...