Personally , i am FOR the reptariums. I use reptariums as well, and about the only problem i have with it is the zipper. It doesn't really rip off, it just gets stuck sometimes. If it breaks of, or if you somehow manage to rip your reptarium( i don't know how), you can replace the screens for about 20 bucks( depending on size).
I let my circkets loose in the reptariums, but i have never ever had them chew through the mesh. It is also very a light-weighted cage, so it is definately a plus if you want to move it around.
Reptariums also use reeinforced nylons that is stronger than alluminium. Reinforce nylons is non-abarsive and is less likely to cause nose rub damage to your reptiles. personnaly, i find the mesh to be very hardy. and also, like it was aforemention by some users, it does provide more privacy for you reptiles. Definately a plus for your chams.