Been a while since this topic has been posted on but though it would be of interest to some readers. I have seen a continued improvement in the performance of LR, the use of smart previews to speed up develop module has been great. Its still a bit clunky when zoomed in but overall performance is acceptable with the 5Ds. I have recently tried On1 Photo 2017 to see what it can offer… Not ready yet IMHO. It looks promising but it makes Lightroom look fast, it is so slow on export and switching between modules, not useable for a professional edit yet. Image quality is again different to Lightroom and while it is better at noise reduction due to the control on offer with shadow, mids or highlight protection it does not seem to be able to extract the same level of finesse and detail from the image as LR can. Some of this is perhaps due to my comparative inexperience relative to LR but the speed of operation and basic set up is too painful for me to continue evaluating for now. At the moment Adobe keeps my custom as I feel it offers the best all round package, including sheer performance (which it pains me to say in light of the original subject matter for this post) for my needs. Still hoping for a big performance boost from LR in the future though.
Ben