I would not say that one is better than the other.
I will say this: I would find it difficult to make a comparison between the two, just for the sake of saying "this one's better than that". However, there are some features that both have or lack.
The RNP is definitely something very different. As I've mentioned before, it has an amazing "openness", or top-end that gives the impression as if your hearing has been extended forever. Not so much of an "EQ" kind of high-end, or high-frequency boost. Almost seems psycho-acoustic. The RNP really brings your signals "up front", but not in an aggressive, rude way. Signals behave well through the RNP. The DI feature alone is quite remarkable. I tried bass guitar, electronic drums, keyboard and even plugged in an SM-57 to the DI input... very, very nice. And ya get 2 channels for under $500. Definitely in the value-busting trend of the RNC. My only complaint is the gain knob (actually switch). It feels very awkward; a bit too tight... almost feel as if I have to turn it very slowly... but I guess its not as important as what comes out of the box, for most users. I am sure FMR Audio is building these units with much precision.
Now the Sytek. A great value if you get the options on Channel 3 and 4. Very clean, fast pre-amp. Excellent if you'll be doing drums or recording classical music... or if you're just looking for a nice, clean, transparent pre-amp. It is VERY detailed-sounding. It is about as sonically close to Earthworks as you can get, one reviewer said. These pre-amps used to go for $1200-$1500 just 2 years ago. The reason you can get them for under $800 (according to Mike Stoica himself) is that the design is already "payed for". Mind you, this unit has been out for a few years already. It's not a new piece of gear. The MPX-4aii is a no-frills unit... all you get is mute, phase, and 48v push-buttons for each channel. No insert capabilities either. In the rear, you get XLR in and XLR out for each channel. The unit feels very solid; great build quality.
If you're looking for something flexible, and transparent, and could do without a DI input... I'd recommend the Sytek with the Ch. 3/4 options.