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I've had an RC8 for a bit over a year now. My basic Cheshire eyepiece is useful to get collimation good enough for deep sky imaging (ie nebulae/clusters). My Cheshire eyepiece seems to be at least as good as or more accurate than using the LiveView method. As long as collimation is quite close to perfect, I find that in practice, seeing is the dominant contributor to star FWHM, and that any eggy stars are down to bad tracking, not collimation.
The only thing I've needed more accurate collimation for is planetary imaging (using a 3x barlow). For this, I've found that a Cheshire eyepiece alone is not really accurate enough. Instead I use MetaGuide to make the final tweaks to the secondary with my imaging webcam and barlow in place. It was a bit of a struggle to get used to using MetaGuide at first, but it now seems a fairly quick and reliable method.
The good news it that my (carbon) RC8 seems to hold collimation pretty well, which is one less obstacle to good imaging.
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