This is an interesting topic and sort of coincidental for me because I've been thinking a lot about nectarines the last couple weeks.
I agree with all the comments that nectarines are indeed what I would call more "intense". I have 18 trees of nects and have pretty much made the decision to get rid of them. I don't know if anyone would be interested, but I'm speaking strictly from a commercial viewpoint here.
From that perspective, nectarines don't seem to work commercially for me.
One issue is that they don't yield very well compared to a peach, which seems to stem from their relatively smaller size (although fruit set also hasn't been what I'd call great for most of my nectarines).
Another problem I have is that while the biggest and brightest nects are intense in sugar and acid, many of the smaller or a bit more shaded nects (on the same tree) are a bit too tart. So what I can sell as #1 fruit tends to be a small amount.
The last issue is that nects are hard to sell at the orchard. The skin is rarely very pretty (although Summer Beauts were beautiful this year). But most people who come to the orchard just don't want them. This is probably something somewhat unique to my locale. In my locale, people are used to local peaches, or they don't even really know what a nectarine is. At farmer's markets in the city, people are a little more adventurous and they sell a little better.
Again, this is purely from a commercial viewpoint. As a homegrower if I could get the brix high enough on most of the nects, I'd probably try a few. In fact, even commercially I may not get rid of all my nects. For now, I intend to keep at least Summer Beaut, Nectafest and possibly Silver Gem. Silver Gem produced almost nothing for me this year (a challenging weather year). There wasn't hardly enough fruit this year to evaluate much, but in the past the fruit has been exceptional.