Well, I have demoulded the Envirotex item after well over 30 hours in the mould.
There was obvious shrinkage of about 6-7%. Easycast Clear shrinks less than 1% in this same mould.
The results are mixed I'm afraid.
The Envirotex has a slight yellow tinge and almost no smell. It is still slightly soft, can be easily bent and permantely marks with a fingernail (Easycast clear does not). All surfaces are very clear, giving a good view into the interior.
There are many hundreds of pinpoint airbubbles throughout the object. These in my opinion are good enough for something that would sit on a desktop to show something to a mate, but wouldn't be good enough for scientific research or display. It would look terrible under a microscope.
Anyhoo here are the pics:
Thoughts: Envirotex may not be good enough for your needs if for scientific display; it is cool when curing. Easycast clear requires pressure casting which you may not have access to and may damage the insect (?); it also heats up to about 50degrees Celcius when curing. My Dad and brothers' had much better results imbedding mineral specimins with acrylic resin, though the heat factor may be a problem with delicate insects; acrylic can get hot!
Sorry for the results, I hope this has helped though