Couldn't decide whether to post this here or in the invertebrate section...

I'm trying to decide what kind of roach I should get if I want really really really big feeders. I'm feeding a savannah monitor, he's eating large nymph dubias right now and I want to get a colony of something larger going before he outgrows them.
I've got time to nurture a small colony into a very large one, and plan to maintain a large tank so I should have enough adult breeders to produce lots of feeders. However a savannah monitor can eat 30+ roaches at meal time so I do need a lot of feeders twice a week.
The main thing I want is a extra large roach so that I can feed 20 -30 appropriately sized ones instead of 50+ little ones. Also bigger feeders are easier for a large animal to catch... ever see an adult beardie trying to catch crickets, lol. :}

Anyways.
The ones I'm considering are:

Gromphadorhina Portentosa (Madagascar common hissing cockroach) up to 3 1/2inches in size.. downsides... good climbers, shell too hard? slow breeders.
or Gromphadorhina oblongata , (Madagascar Giant hissing cockroach), 4 inches... same issues as the common.
Monitors are pretty strong so I'm sure he could crunch the hard shell but would he have issues digesting them?... anyone know how big nymphs get, before the shell becomes the hard as an adult?


Eublaberus distanti, about 2 - 3 inches, really meaty. slow breeder. I had a hard time finding info on these. And my dubias get to be 2inches so I don't know if these are big enough


Blaberus giganteus, 3 1/2 inches. Can kinda fly. These sound pretty good but I can't find any good suppliers.

Or if someone knows of a better roach for my needs please pipe up.
Also had anyone bought from theinvertshop.com ? What did you think?

p.s. yes I posted on arachnoboards too. lol.