The price goes like 10.33 promo < 10ES2 promo $580 (I'm not sure if it's still going on) < NFB-28 $680
Right now, it really depends on how you're going to use it. If you're going to use the extra inputs and outputs of the new case, 10.33 and NFB-28 should be the ones to consider. The new case with volume knob is fancy, but people like myself wouldn't need it because I just use the DAC outputs to another headphone amp for listening, and my desktop speakers have volume control.
If you're only going to use 1x RCA and XLR outputs then the 10ES2 still remains as a very high cost performance unit that I recommend (if the promo is still there), you will not really find another balanced ES9018 DAC/amp with excellent USB (the USB-32) and TCXO upgrades available, for a similar price. If the promo wasn't there, I would have got the NFB-1.32 as I just use the 10ES2 as a DAC since Kingwa mentioned the DAC outputs sound pretty much the same.
The other obvious difference is DAC chips, either dual WM8741 on the 10.33, or ES9018 on the 10ES2 and NFB-28. If you want that last 5-10% of detail, clarity and extension on the treble and bass, then the ES9018 models win, imo. I would choose the WM8741 models if you prefer more smoothness between notes. All the WM8741 models of Audio-gd I had before, they gave a nice and relaxed listening experience. Eventually, just curiosity for more detail and extension brought me to ES9018 models, and I'm very happy with the 10ES2 so far. I probably wouldn't go back to WM8741 models atleast for a few years, but that's just my preference.
Anyway, it seems you're going to take your time choosing one, so by the time you're going to pull the trigger, something else may be out... maybe you don't have to worry too much now, just decide when the time comes.