I've been shooting cedar shafts for awhile now and just tried a test kit of surewood shafts.The cedar shafts are 60/65 and the surewood are running 50/55. Any body seeing these kind of results. My bow set up morrison cheyenne  57@27.5. Arrows are 29.5 " 145 grain tip with 3 5" feathers .

Do you check the spine yourself? Or just go by what they say?

No. I always find the Surewoods to be right on the money as far as spine weight and mass. I would think that both weights would not be right for your bow. I would go with 65/70's(that's if the draw length of the bow AND your draw length are both 27.5"). I'd also cut those down to 29"bop with that draw length, maybe even 28.5" if they tune well to that length.

You may be seeing some discrepancies between spine testers and different shaft suppliers or sources, but that is an unusually high variation.

That's the beauty of the test shaft packs, for example if a Surewood test shaft of 55/60 works for you then you can bet the matched Surewood shafts of the same spine also will.  They will match and once you know what the bow likes you're set.  

I am trying my first batch of Surewoods and have found them to be a tad stiffer than my cedars.  Both are 55/60.  I tried them in a more centershot bow and they flew perfect.  I really like them!

I like the surewood shafts just fine . Never seen any shafts straighter.  I'm finding that  the lighter shafts  shoot the same as my cedar shafts that are a heavier spine.