It depends on your workflow. DXO only works on raw files. I send the raw to Photolab from lightroom and it returns me back to lightroom with the dng. So you now have the original raw and the DNG in lightroom. From there I keep the raw but work on the dng. I end up in photoshop, so in theory i could discard the dng since it is a layer in photoshop, but I keep it just in case. Storage is cheap these days, but the dng files are probably huge.
You better have a reasonably modern computer with at least a fair GPU. I had a problem with an outdated driver for my graphics card, so DXO was working only from the CPU. It took 9 minutes per photo to run deep prime XD using the CPU only. Once the driver was corrected the same file took 1 minute 18 seconds. Still there is some waiting time but with Photolab you can keep working in lightroom on other files while it is spinning.
Even if the file is not noisy I like the lens corrections part of DXO and the way the colors are rendered in DXO. If you don't run the deep prime noise reduction, just do the regular denoise, it doesn't take as long, maybe 30 seconds.