ONP Reviews and Articles:

IGN's Mod Watch: ONP

UnrealSP's Map-By-Map Review

UnrealSP's Full Review

UnrealSP's SpeedRun Guide

Krycha's Review @ ModDB

Some quotes from reviews, emails, forums:

Tuco
"The best single player modification made for UnrealTournament"

DaBeowulf
"Words(and pics and vids) don't do this justice: D/L!!!"

Apex
"Unreal should have been ONP. This is probably one of the coolest single player games I've seen..."

Hellscrag
"I don't normally use such a superlative. But that was AWESOME! Totally nuts. Such l33tness cannot be permitted!"

Candy Man
"To me this is a masterpiece! [...]The finest Sp Mod out today for UT!"

Slo*Dragon
"The only word I can Think of is "Awesome"..."

Satch
"I fully pay for your work, ,just the demo was cooler then many of the shite games I've recently paid $50 for,
... anyone want a copy of Renegade?"

Manson
"Oh my [censored] god!!!
Astounding! Amazing! Astonishing!!!!
More memorable than Unreal1! A LOT more memorable than Return to Na Pali!!!
Freaking amazing work man, this is what RTNP should be instead of that [censored] mission pack...
... and it's free! :-O"

Cy Torgerson
"This modification is the BEST single player campaign I have ever played!!!"

Fuzzman
"The demo was f@#king awesome."

EXplosive
"What ONP is doing is great and the work is among the best in my opinion."

Francois
"It has the original Unreal feeling in it... but even better... The atmosphere is great.
The player feels so implicated in the story..."