Hi - late to this party! I love Lightroom, but as my job produces ALOT of RAW's , i swear (nearly 20yrs experience) by using Photomechanic first to build superfast previews (much much quicker then letting LR do it), make an initial selection there, and THEN import in Lightroom....
Cheers
Kev
Photo Mechanic gets its speed from displaying the previews embedded in the RAW file and doesn't normally render the raw files
From Camerabits help
Photo Mechanic is designed to be able to preview the files produced by cameras from most major camera manufacturers.
Generally, these are proprietary RAW formats (Canon CR2, Nikon NEF, etc.), or compressed formats like a JPEG. When viewing RAW files, Photo Mechanic displays the JPEG that is embedded in the RAW, as this allows for the fastest browsing experience. It is also possible to use Adobe DNG Converter to render a preview from the RAW data, though this option is rarely needed and comes with a performance penalty.
You can now select using embedded JPEGs as an option in LR, and Capture One automatically uses embedded JPEGS for culling before ingest.
As far as I am aware, LR only uses the embedded JPEGs for pre-import culling, and until it has built its own previews.
Capture One, on the other hand, after ingest, allows you to reopen the "culling" view, where it reverts back to using the embedded JPEGS, of the now imported files, for faster scrolling through large numbers of files.
Which is ironic because Capture One is faster at displaying its own previews than LR is, and reverting back to embedded previews isn't as useful as it would be in LR.
Overall, PM is still a more robust choice for culling large numbers of files, but C1 and LR aren't as far behind as they once were. I've been using PM for a fair bit more than 20 years for culling and captioning
But, great as PM is, as I'm now retired, I felt unable to commit to the new subscription model, and I'm now doing my initial culling with Fast Raw Viewer and then importing into Capture One.
I'm actually find FRV better than PM for culling, but neither LR nor C1, can match PM for captioning and general file management/organisation.
FRV allows you to compare 4 images at the same time, unlike the two images in PM, FRV allows you to adjust the exposure, which makes selecting the best shot easier, something you can't do in PM, and it displays a raw histogram. Small things that make a big difference when trying to select a "best shot".
With PM, I had FRV set as the editor (cmd+E) to take advantage of these tools while doing everything else in PM. And FRV + PMPlus+ Capture One sessions would still be my preferred approach, if I could afford PMPlus :-(