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Ken, the reflection is normally used in Newts etc, but those lasers can be used for refractor collimation, in fact i used a very similiar one when i built my iStar 127mm f12 refractor. So yeah use an objective target which you have centre spotted, and your Cheshire to align the donuts so that any objective tilt is negated.
I guess you might be able to use the laser reflection but be very sure your laser is actually collimated correctly itself (ie it shoots straight). It is pretty easy to collimate a laser, and there are numerous threads about how to do that, so I won't go into that here.
Also, one other thing, make sure you rack your focuser in and out its range when your collimating to the centre spot on the objective, so you can find any focuser misalignment throughout its range of movement. Some focusers do not rack straight. I had one on a RC which wandered from one side of centre to the other.
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