Several years ago, after having purchased the Celestron C5, I enjoyed the ergonomics of the SCT design so much I opted to purchase an 8" SCT. Celestron offers two versions of their 8" SCT, the regular C8 and the 8" EdgeHD, which has corrector lenses in the baffle tube that correct for the comma and field curvature present in the normal C8 (and SCTs in general). This results in a wonderfully crisp view across the entire field when using a low power eyepiece. The center of the field is probably not much difference between the regular C8 and the 8" EdgeHD, and you can add the reducer/corrector lens for about $100 to the back of a regular C8 to get most of the gains in the outer field that the EdgeHD has, but the EdgeHD is still better. This scope gave me the best views of Saturn I've ever had in any scope, even beating anything I've ever seen in a C14. That isn't a fair comparison though since a C14 is capable of showing a much better image, but during the times I've used a C14 the scope was never in thermal equilibrium. Since SCTs can take a significant time to cool, an 8" SCT will reach equilibrium and start providing sharp images much faster than a 14" SCT. Additionally, a big advantage of scopes like an 8" SCT is that they are compact and easy enough to set up that you are more likely to use them frequently, which in turn gives you a better chance to be out on one of those nights when the seeing is really superb.
The fit and finish of the Edge HD scope are similar to a standard C8, though the color is different and the Edge HD includes two vents in the back of the scope to help the scope cool faster. Third-party vendors make fans that fit into those vents, which can further speed cool downtime. The focuser on the Edge HD is the same as on the standard C8, though the Edge HD version does include mirror locks which can help when doing astrophotography as it prevents the mirror from shifting as the scope is moved.
The Edge HD scope weighs slightly more than the standard C8 since it contains an extra set of lenses in the baffle tube and has mirror locks. However, the extra pound or so of weight won't really impact your mount choice.
The combination of a C5 and 8" EdgeHD was really nice, and probably I should have left well enough alone, but eventually decided to go to a C6 and a larger SCT. However, work and family changes resulted in that larger SCT purchase never happening, and the C6 serves we well enough as a middle ground scope for now. But, I do miss the views through the 8" EdgeHD. I highly recommend the scope if you are looking for something in that aperture range.
If you are looking for more information on this scope, I recommend reading Celestron's white paper on the scope: https://bit.ly/2GPt8Hl
The regular C8 is a nice scope too, and the 8SE and Evolution 8 are great options if you don't want to spend the extra amount for the EdgeHD version.
You check out current prices for the 8" EdgeHD from Highpoint Scientific or from Amazon here: https://amzn.to/2R2kS9K
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