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The Orion one only inserts a short distance and is not a well-designed tool. It cannot get close enough to the secondary.
The Celestron is a far better tool.
And the Astrosystems Light Pipe is better still.
All of these tools are "Combination Tools", combining a Cheshire (pupil on one end, bright reflective ring with dark center on the other) and a Sight Tube (pupil on one end, crosshairs on the other).
A pure Cheshire has no crosshairs.
Lasers duplicate the function of a sight tube for secondary mirror alignment.
A Barlowed laser duplicates the functions of a Cheshire for primary mirror alignment.
A laser by itself should not be used for primary alignment because you won't put the primary alignment in tolerances.
Collimation tolerance for a primary mirror is 0.005 f/ratio³.
At f/5, that is 0.63mm, which is finer than the laser beam.
A Cheshire can align to a greater precision because the error is magnified 2X.
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