1.) US Army Rangers are NOT Special Forces, that is the commonly referred to as "Green Beret", and I have never heard an SF troop call themselves Green Berets.
2.) US Army Rangers are considered part of US Army Special Operations Command as well as SF folks. There is a difference between the two.
3.) Combat Arms encompasses quite a few MOS'. None reach the level of being "as close as it could get without being SF" other than being SF. That is an affront to the dedication and training of SF soldiers. That is NOT to say the other MOS's within CA are not tough..or less important.
4.) Physical demands placed on SF troops are a bit more than 5%. They are huge! I would agree that the mental fortitude required to complete training and become operational are great, but if you are not fit, you will not make it. Fact.
5.) Rank. It is true you will make rank quicker in most Combat Arms MOS'. Especially true to Special Operations Command.
6.) US Army Rangers are an impressive bunch and I am proud to work with and support them on a regular basis. I have seen first hand their sacrifices and efforts..they are no less than heroic. They are as dedicated as you will find to their craft. They are proud, proficient, and effective. They do the tough work and get results..day in and day out.
7.) To the OP, if your kid is seriously considering becoming a Ranger. It has to consume him. He will need that drive to complete Ranger selection. He cannot think " I think I will give this a shot, sounds cool." It is a cool job but the demands it places on an individual are not for those not having the conviction to do it.
8.) As for getting a job when he gets out, there are no Army Ranger jobs in the civilian world. There are Cops, Security (private and public), there are contractors, federal law enforcement (plus CIA). They have unique skills that require unique employment. Something to consider.
9.) Have him talk to a "no shit" Ranger, preferably one with combat experiences. It may open his eyes....wide.