Well...that was a disaster. At the range, the parallax was stiff as hell and the focus was inconsistent. Once I got it focused, every single shot would cause the image to go blurry and I'd have to re-focus. Turning the parallax knob back and forth on the target at 100 yds, the ideal focus would be at ever-different points on the dial. I decided I had too much torque on the rings, causing the parallax to be in a bind. I had torqued the Spuhr rings to 25 in lbs as I always have on my other three SB 5-25s, also mounted in Spuhrs. Yes, I used Loctite and I know that increases the actual torque value, but it has never caused a problem before for me. Back home, I loosened the ring screws and experimented with different torque values on the screws. Even at barely-snug the parallax knob is still stiff and the new design has fairly sharp edges causing it to bite into your fingertips as you try and turn it. The Loctite is now dry, but I found any torque above 10 in lbs caused the parallax to drag, so that ideal focus came at different points on the dial as I went back and forth rotating it. The force required to rotate the parallax knob is also WAY higher than the three SB 5-25s and the NF 7-35 ATACR I currently have. Something is just not right here.
UPDATE: I sent it back to SB (Virginia) on Tuesday, week before last. They received it two days later on Thursday. I got a call on Monday of this week that it was going to ship out back to me that afternoon. I received it yesterday, so including shipping both ways it was a 15 day turnaround. I asked what they found. He said they disassembled it, checked that everything inside was to spec, re-assembled it carefully to spec, and everything worked fine, including mounting in a Spuhr mount torqued to 25 in lbs, since that is what I have. I asked if they tried to reproduce the problem before disassembly and he said no. I asked if it was possible that the original assembly process in the factory could have been "off" somewhere, and that simply taking it apart and re-assembling it carefully/correctly could have fixed a problem and he said, "Yes, it's certainly possible." I was a little disappointed they didn't test it first, witness the issue, then retest after the repair. Then I would know they identified a specific problem and corrected it. But as it was done, I was a little leary that I would get it back with the same problem since it was never identified.
I got it mounted last night, torqued the rings to 22 in lbs with Loctite, which would put it closer to the specified 25, and tested it this afternoon. It was definitely MUCH better, but I think I can still detect a "little" backlash in the parallax focus. It may be just me being overly-critical because I'm overly "focused" on the issue (pun intended), and the feel of the new design is much stiffer than the 5-25s I'm used to (as noted by virtually everyone who has handled a 6-36) . Before, when I was focusing on a 100 yd target, going from near to far, the target would come into focus when the dial was around 200. Going past that and then reversing the direction from far to near, it wouldn't come into focus until the dial was around 50. Once focused, firing a single round would immediately knock it waaaay out of focus. Before sending it in I tested the theory it was due to the rings and found that the problem went away when the ring screws were 10 in lbs or less, but returned at any torque above that.
Today, the 100 yd sharpest focus came in right at 100 as it should (although I've never worried about the number on the dial exactly matching the exact distance, as long as it was consistent every time). The new parallax knob on the 6-36 has a smooth-faced notch for each of the numbers (a notch for 50, 100, 200, etc). The rest of the dial is knurled except for these notches. The only thing I noticed was that going from near to far, the pointer next to the dial would be at the top edge of the notch for the number (100), and when going from far to near it would be at the bottom edge of that same notch. Once focused, rotating the dial back and forth the width of the notch for 100 (Maybe 3/16" of rotation? I'll have to go look at the width again) had little to no effect on the fine focus, so maybe just a little backlash there, or maybe all my others do the same and I've never noticed because they aren't as stiff to turn. The great news is that it focuses easily and no longer goes out of focus when the rifle is fired, and I was able to zero the scope at 100 with no issues whatsoever. I wish I had another 6-36 to compare it to - it may just be the nature of the beast, as I am told the new parallax knob is much stiffer than the older design on the 5-25s I'm so used to. In any case, it seems to be working fine at this time and I think the problem is resolved. I will know more when I get to take it out to distance this weekend (I only have a 100 yd range at the house).
I was very satisfied with how SB handled the problem and the turnaround time. I have some doubts as to whether or not they might have actually found the problem and just didn't disclose it while quietly fixing it, or if it was just a simple case of taking it apart and re-assembling carefully was all that it needed (I had a brand new Forster Ultra seating die in 300PRC recently that was exactly like that. The traveling inner sleeve was binding and would not fully extend when released after being compressed. I took it apart, didn't find anything wrong, re-assembled it and it has been perfectly fine now for 300 rounds loaded).