John, I'm running those on my daily driver... no such issues on this end. If you're seeing glowing headers even at idle, then EGT's must be way over the top... what's the AFR like on the motor? Aren't high EGT's directly related to A/F ratio?
As I said, I have no such issues with mine... very pleased so far.
'89 911 Turbo Cab
Protomotive MAP ECU, Twin Plugged Heads, GT2-EVO CAMs, 3.3L fully finned P&C's, ARP fasteners, C2T head gaskets, Titanium Retainers, Turbo spec valves, springs & guides, 964 splash valves, GT35R BB turbo, GSF Stainless Headers, Magnaflow Exhaust, Full bay Intercooler, TiAL 46mm w/gate, TiAL 50mm BOV, Apexi AVC-R EBC, SPEC Stage3+ Clutch kit, Crane CDI Ignition