Considering we all have different opinions as to what makes a good RAW developer none of them can be considered the best for everybody. It is entirely possible that Photo Lab is the best for the greatest number of people. If so it could be argued it is the "best".
I never use a RAW developer for cataloging because I have my own system and use FastStone. Also, all my cameras are well-supported. Based on that I would say that for me DXO Photo Lab is the best RAW developer. Back when I used Lightroom I turned off its cataloging feature. I could never master its noise reduction to my liking. After a photo shoot, I transfer my RAW files to a hard drive, Open them in DXO, and batch-process them all in PL6. As far as I can tell PL7 doesn't offer me anything I want over 6 so I'll wait for PL8 next year to upgrade.
Can you explain how you were able to edit files using Lightroom by turning off its cataloging feature?
It's been a few years so I don't remember exactly but there is a way of doing it. Somebody on these forums actually showed me how. I have my own system of folders and subfolders arranged by Year, month, and event. I was able to allow Lightroom to let me search the folders my way and not Adobe's way. By searching for the proper year and month I can access any particular file or files I want for editing.
You could do searches but at this point I'd have it is impossible to edit a file in LrC without importing it. If it is not imported it will not show up the LrC folder library thus you can't do anything with it.
Here is my LrC library.
Here is the OS and Canon DPP. I could open any other developer and see this same thing. The only reason years 2006 to 2010 are missing in the LrC library is because I didn't start using Lightroom until 2011.
If I wanted to edit files, folders or a particular year between 2006 and 2010 I'd have to import it.
All those files by year are on an external drive. I decided I wanted to edit some files from 2007. I found that folder in Canon's DPP and dragged it to my desktop. I could have used the OS as well. It does not matter whatever you because one mirrors the other. Same goes for LrC. If I move a folder that is in the LrC library that will mirror in the OS and DPP.
That folder has been imported into LrC and I can now edit the files. Since I imported from the desktop and did not give it any location instructions it remained on the desktop. Using LrC I would normally drag that folder into one of existing years in LrC library or create a new folder called 2006. Again that change would be mirrored in the OS and DPP. LrC would have automatically moved that folder off the desktop and to the external drive.
Since I dragged that folder from the external drive it copied it (not moved it) so now there are two sets of that folder. What I did was not typical as it was just an example. To keep things tidy I'm going to delete it from the LrC library and it will still be there in OS Library.
The reason for importing files is so LrC's DAM can function correctly. It needs to read the metadata and most importantly it needs to know where the files are located, which can be anywhere.
In case anyone thinks this complex it is not. This was because of the examples. It is simple. After a shoot I plug my card in and pre-cull my files using Canon's DPP. When done I create a folder, drag those files into it and import into LrC.
After the previews are built I drag that folder into the appropriate year on the external drive. I do this using LrC, not the OS. Since LrC moved it, it knows where it is located and I don't have to worry about it. I could also instruct LrC to automate those moves if I wanted to.
A few times I used the OS to move folders but that that was for tens of thousands of files. Replacing an external drive for example. The OS is better at moving a mass amount of files. When that is complete you just have to let LrC know where you moved them.
I have been to this way since 2011. With all the version upgrades which included catalogue upgrades I've never had a single issue.