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Miklos - They are both great focusers for the money. I have three GSO Crayford-style focusers for some Newtonians lying around and they are mechanically very smooth - especially with the 10:1 reduction. I have the WO unit for SCT's actually attached to my home made refractor at the moment and it is a great bit of gear too.
There was a complaint running here on IIS a while ago in relation to a WO SCT focuser being "out of collimation". As the owner released the rotation lock and spun the focuser a laser colimator's beam moved in a circle around the center rather than on its own pin-point axis.
I should have had a longer thought about it back then and mentioned that I think I know what the problem was now. If you take apart a WO focuser, there are three screws around the periphery of the main barrel that physically hold the rotational part of the unit to the front - where the SCT threaded static portion is. These screws adjust to provide rotational resistance and eliminate slop. If taken apart, the three screws MUST be screwed back in properly - i.e. same number of turns each. If this is not done properly, the rotating part of the focuser can be left off centre - causing the centre to shift as it rotates around its own axis. If you leave these screws alone, you won't have any issues.
If it were my need to get another focuser, I'd go for another WO without hesitation - they are beautifully machined (like all WO gear) and will last you many years. The only shortcoming of these focusers is the overall length - as they can cause a camera to collide with the base of the forks if you aren't careful.
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