I've read several dozen threads on regulators and I'm still uncertain the best course of action, so I burden you with one more thread on the subject.
Background: My son has waited his entire short life to get into diving. His mother and I were very active divers before he was born, but we took a break from diving until he was old enough. He was certified last month in Maui, and we have been diving local quarries once per week since returning. We plan to resume our pre-parenthood dive schedule of 3 - 4 dive trips per year, and he is 100% over the moon about diving.
Type of diving: There will be ZERO true cold water dives. My opinion of what counts as cold water is pretty much "anything under 70F". Our diving, historically, has basically been a blend of 3 different locales - quarries in the southeastern United States, wreck dives off the coast of Florida, and the vast majority of our diving has been tropical (Caribbean and Hawaii). If the water is cold enough to need to pull out my 7mm, I'm more likely to spend the day sitting in a hunting blind rather than diving. Given my son's age, it will be some time before he could seriously consider tec diving.
What gear we already use: I'm trying to kit him out with quality gear that will last many years to come. As of last weekend, he is diving with his own Halcyon Infinity BP/W, Hollis F1 fins, 5mm Bare ultrawarmth boots, and a Tusa mask. He's using my old Oceanic VT3 computer, and we will move the transmitter from my reg set to his so he can go air integrated once he has his own rig.
What I'm looking for: He has expressed interest in buying his own regulator set, but I don't think he has enough funds to cover the cost of one and I really don't mind buying gear for him. Either way, he's a bit more price sensitive than I am. I want to get him a quality set that will last him decades. He does want to dive long hose (like I do), but I'm a bit uncertain if I should get him a 5ft or 7ft long hose, as he's only about 5ft tall right now. I'm looking for a 1st & 2nd stage, backup 2nd stage (short hose w/ bungee), and an SPG.
Brand preference: I'm a bit unhappy with our Oceanic 1st stages that my wife and I dive with right now. Both have had failures (after being serviced) leading to excessive IP causing the octo to free flow. One is at the shop right now waiting on a new seat, the other will be dropped off this week for similar repair/rebuild.