Recently received some of Ring's blue guns, and of course they are excellent and beautifully detailed.
All my experience is with real guns, and with aluminium castings, so I did notice a difference from them in the plastic blue guns, that relates to making holsters.
Clearly, for the intended purpose of training, the trigger guards of some if not all pistols have been beefed up, likely to keep the guards from breaking during, for example, gun take-away training. The below pic shows the added material marked out in silver paint:
The amount of material added is substantial from a holster-maker's standpoint: if these blue guns are being used for hand moulding / boning (likely wouldn't live long through press-moulding, even aluminium ones can break during this), any deep moulding into the trigger guard will be different from that done using aluminium castings, which are slavishly made to have the same trigger guard dimensions as the real thing. We don't use the real thing in press moulding because they'll crush.
I'm not saying it's either a good, or a bad thing; but will say that this combination -- a blue gun and hand boning -- might make a material difference in the gripping of the pistol by the holster, if the holster relies on hand boning to retain the pistol; such as a strapless shoulder holster (classic Seventrees shown):
Or even this contemporary Galco belt holster, though gravity is certainly on our side here:
Hope that helps.