If I can say anything conclusive, I've had poorer behavior/sociability from the animals in opaque containers, containers below eye level, and from containers where I access from the top. My Uros have a penchant for watching things (and each other) and utilize all open/transparent surfaces. If you have adequate/proper hiding places for the animal it might flee but I don't see why an transparent container would otherwise be less "secure".
I've seen the best behavior from animals at or near eye level, transparent panels, and accessible from the front. For new/acclimating animals, covering sides of a transparent container with paper temporarily, followed by gradual removal, is not a bad thing.

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uromastyx geyri (Saharan/Nigerian), hardwickii (Indian),
macfadyeni (Somalian), ocellata (Sudanese), ornata (Ornate), benti pseudophilbyi