I bought my jig with a straight clamp and have since bought left and right wing helical and never swapped the nock receiver. I've had no trouble, but am curious to hear what others say. Since we spin the arrow 360 deg, I can't see how the nock receiver can be different for different clamps.
I just happened to have changed my bitz nock reciever from left to straight. As I compared the detents between the two I couldn't find a difference. When I think on it some I can't see why there would be really - basically what kenn1320 is saying, it's all about stopping at certain points on the 360 degree rotation.
Makes my wonder why I bought the straight receiver now. I think you can use a left, right and straight clamp just fine with one receiver.