How does your G17 fit in the Recon kit? A lot of extra room or is it pretty tight? I'm looking at those and the snubby for hiking.I have the recon kit bag and I wouldn't get anything smaller than that. It has the molle front, mine is maybe 8 years old so I think they've made some changes since then. I wanted it that way so I could scale it up by adding some molle pouches or mag pouches if I wanted to make it into a basic ready rig. You could also get the regular kit bag if you wanted more capacity, but I planned mine as just to hold the bare bones
In terms of the kydex trigger guard, yes, that is needed because I have purposely tried to pull the trigger through the kit bag and it is possible, though unlikely. It's well worth the insurance in my opinion because I only carry chambered. I didn't get one from them though, I don't remember HPG selling them back then. I bought one from Raven concealment, the VG2 or something, basically in a pinch it could he used as a IWB holster on the hip if I wanted to switch and take off the kit bag to draw even less attention.
The reason why I say the HPG chest rig is best, is because you will find it far more useful than merely holding a gun, you'll sacrifice maybe half a second draw time for significantly more usefulness and concealability.
I use mine when I torture myself jogging the neighborhood. Full size G17, wallet, phone, keys. Spare mag if I feel like it. Basically none of it has to be in my pockets which would suck. I've also used it a lot fishing when hiking. You can keep some small necessities and the pistol easily accessible and walk around without needing a pack.