RE: What is the prefered bypass/pipe set-up?
Scott
Without any doubt 'A' if at all possibe. It has many benefits, amongst these; as Darryl said - it's better during a hot start and flame out. Fire extingishers can get pin pointed via the intake ducts. The bypass also acts as a fuel and smoke oil catcher and prevent these type of leakages getting into your fuselage and radio installation. One such leak and the next time you get a hot start, you've got a fuel primed fuselage 'wick' to burn. It also prevents servo leads getting blown on to hot turbines and pipes as happens during the 'hurricane ' without a bypass. Even secured leads can get blown loose by the uncontrolled air flow. If it's to be a quick jet, a bypass is a must.
Even just using the bottom halve of a bypass ducy is better than nothing, for some obvious reasons as mentioned above. Afterall, it only take afew minutes to open the bypass and check it for any fuel leaks whilst at the same time you can check the glow plug and general connections to your turbine.
The effort in planning and perfection of installation, far out weighs the the misery of a burnt out jet.
Cheers
Springbok Flyer