I have the core 51, dont use the core 100 but have 3 chronarch d's, same thing but aluminum frame.
I actually used one this past season on a cranking rod, but for lipless cranks, so the fast gear ratio was ok. Other than that they've held up great, no problems. Would buy again.
As for the gl2, id also take the Crucial series over the gl2. Or if you dont mind spending a bit extra,
Dobyns 704 or 705 Glass, my favourite cranking rods.