Hi,
I can't tell about about that specific GBIC but have seen different Cisco and HP ProCurve GBICs working very well in Juniper equipment, in particular with EX 2200 switches.
Please note, that Juniper tolerates the use of 3rd party GBICs (i.e. it doesn't block use of non Juniper parts) but does not support them. If you experience problems and call JTAC, they could request you to swap them with Juniper equipment and reproduce the problem.
Regards,
Dominik