The advantage of RAW+ is that if you look at the JPG and are happy with it, you can delete the RAW
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With all due respect, I would recommend against this. Every time you master another aspect of your PP program, every time a new features is added, you may want to change a file. I find every time I'm ready to reprint a picture because we sold a copy, we revisit the file and invariably we want to make changes. In one of the TV shows on Ansel Adams they show the progression of a single print, from the time he first printed it, until 25 years later. Same negative, but a different treatment in printing. Saying a picture is good enough is like saying you can keep the print and toss the negative. The trouble is 2 years later you may not agree with that assessment. And if the negative is gone, you've tossed the information you needed to do something different. Every time we need a new copy of an image, we re-evaluate the PP job we did last time we printed it, and re-evaluate. I have jpeg files used to make previous prints, but at least 50% of the time we revisit the RAW file and change part of the file.
An example would be what happened when Adobe brought out the shadow/highlights slider bars, all the sudden it was very easy to correct harsh shadows with not that much effort. Images with harsh shadows that would have taken hours of care dodging/ burning masking and feathering could be improved with a small movement on a slider bar. If you had a shot you didn't like because you didn't want to deal with the shadows or highlights, and you'd tossed it, you were out of luck.
The shadow detail in a jpg is probably not more than 100 shades of grey. IN a 14 bit raw, it's thousands. The jpeg reduces thousands of, shades of black/grey to hundreds. If you now, 3 years later you decide to bring up some of the shadow detail, on a jpeg it's going to look awful. There isn't enough gradation in the shadows to make it look natural. On a RAW file, you still have the 1000 shades of black/dark grey you originally had. You can pull up natural looking half stop, maybe a full stop out of the shadow and show detail that is not even in your jpeg file anymore. In a jpeg, there are only 16 shades of black, because that is all you need to make a nice image. But it's not enough to store the detail that a raw image has in that shadow.
Like a print, once you've done your jpeg, you can't make much change. You might be able to set your copy machine a little lighter or darker, but doing that won't increase detail. Making it lighter in a raw file will increase detail, and the actual jpeg file will be different. Once you've committed to jpeg, you've committed to 64k, colours and shades. A raw file has millions a 14 bit raw file has 10's of millions.
That's why I use software like Aperture (or possibly Lightroom if you're a PC guy, or like paying for Adobe product) because they are non-destructive. My raw file is stored untouched. Every time they ad something to the program or I learn something new about the program, I can improve my older images. If all you have is jpegs... not so much. And really, what is the cost of storing those images? You can get a few Terabyte drives for a hundred each. I've been going on 1 1.5 Terabyte drive as a back up unit for almost a year now. And I'm shooting thousands of images a month.
I still throw out too much. Every year, I want a couple of images , I don't have anymore because I said to myself "I'm never going to need that." What I've learned is, throw out what's out of focus, throw out 3 of your 5 bracketed images, keep the best two, the ones that have detail the others don't, throw out pictures where you didn't achieve your objective, but keep everything you like in RAW. Give your images time to grow on you. Some of my images I didn't print until months after I took them. They weren't exactly what I wanted, but they were great images. What I wanted clouded my perception of what they were. Once a year go through your drive and get rid of a pile of stuff if you want and throw out what you don't like. But don't do that when you first process your image. And certainly don't let the camera make that decision before you even look at the picture by shooting in jpeg.