Lady, you are right that some people wouldn't have an extra o-ring for any reason anywhere on their rig, and they have a point. I've been back and forth on the subject several times myself.
The Sherwood Maximus is basically like most any other reg, but with a 90° elbow built-in. If you look for some reviews (
here) the one problem they don't seem to have solved is that divers still complain about it still feeling it "pull" because it isn't neutral underwater. They've added a lot of mass/weight to their version of 90° elbow, IMO unnecessarily. My main problem with that reg is that I don't think you can remove the elbow if you decide to later on (if you went to the long hose configuration, for example). I hate re-buying equipment because I either bought the wrong thing or because it was too single-purpose to be useful elsewhere. IMO the Maximus seems to be in the single-purpose camp.
And you didn't ask but I personally have never been a fan of
any of those first stages where the hoses come out on a radial pattern -- around the circumference of the round body of the first stage -- because I think the hose routing stinks. But Sherwood regs are well thought of by a lot of divers, and their designs are pretty well tested.
Anyway, in addition to the 90° elbows (n.b. Scubapro makes a
120° version) there are two basic types of swivels:
- The captured swivels like the Atomics and Oceanics are physically captured and are not going to come apart, though any connection can potentially leak.
- The 360° swivels like this design put too much stress on the connection IMO and are the style you've read about where the pieces separate and the tank empties in a minute or two.
I'm not personally a fan of either of those types because I don't believe they serve a purpose submerged, but some people love them.
If I'm rigging my reg for a strictly recreational dive (<60'), I prefer the elbows because they allow you to move the reg to where you need it to be without the side pull and then you frankly don't need much swivel at that point. The o-ring design is captured; its exactly like the swivel inside your second stage where the hose attaches, nobody that I know of would try to eliminate that.
Just one person's advice who has worked this through pretty thoroughly, but I'd buy whatever standard reg I was otherwise going to buy (I own a handful of Apeks XTX100s regs, if I didn't I would also seriously consider the Scubapro MK17/G250V combination). Then I'd add the $30 or $35 Zeagle
elbow fitting (part #340-1003) on a 40" hose and ask more questions here about the bungeed backup. That way you can remove the elbow but keep your regs intact if you ever change your mind (like I have).
HTH
John