The GEII silicone debate is inconclusive really. If there are mold inhibitors leaching from the silicone, is it detrimental to the health of the fish? One can only assume that its a bad thing, but no hard evidence(s) has been provided to say it definitely does. There are also "hearsay" reports that GEI now also has mold inhibitors. This hasn't been confirmed either as far as I know.
There are hard scientific evidences that mercury is extremely detrimental to humans, yet I've talked to older people who used to play/handle mercury with their bare hands before they knew what they know now. Point is, don't feel that because you used GEII that its an automatic death sentence to your fish.