What attracted me to Production was its relatively low barrier to entry. Just about any duty sized handgun is more than good enough to make GM with if your skills are up to it. I started with a CZ 75, a kydex pancake, Wilderness belt, and four clip-on kydex mag pouches. Placed mid-field (out of typically 40 - 60 competitors) right from the get go. Eventually bought a full belt rig and transitioned to a CZ P-09 which for me has much better ergos and shoots much flatter. The allowable modification are for the most part relatively easy and cheap, at least the ones that gain you the most capability for the $. You can go full retard now changing all the internals, but the advantage that provides is really marginal.
What drove me away was the fact that Carry Optics provides a relatively affordable option with a sighting system that doesn't handicap me (I'm 53 and have had presbyopia for about 10 years) against people with younger, better eyes. I'll put my movement skills against most and I can improve them at relatively low risk and cost, but there's nothing I can do to fix my eyes' lack of accommodation that isn't surgically invasive and expensive.