Personally the grandaddy of Necromunda may have been confrontation, but it spawned from 2nd edition 40k and if you're gonna compare the new updated rules of Necromunda in all of their infinitely expensive and complete uselessness, then i'd say confrontation would have it.
Personally if you want a superior system to the current Necromunda try the last set of Necromunda rules, seeing as at least they were worked on by 3 people as opposed to every bish bosh in the hobby.
And also, the old hard back rulebook, the one I use, has everything there, and the system actually works and answers 99% of people's questions and problems with the current system.
I don't want to hear any responses saying "the new one's better" because it isn't. They've changed about 10ish things from the last one, and brought in 3 new rules, only one of which has any relevance (high impact). The rest is poached off the old book and they parl it off as a new system.
The only REAL improvement is visually, and I will concede that the new redemtionist rules are somewhat improved. However I feel they have spoilt a perfectly fine system by changing something that didn't really need to be when all they needed to do was rewrite it as a new book and put everything the way it was correcting the FEW mistakes it had.
But as always the corporate fools have spread the rules all over

and made it so you need to fork out money to print off the book yourself or pay £20 for an incomplete book and 50 magazines that wont be continued instead of taking time over it and putting it all in one place. GW has done it again. Well done
To summarise, the new book is rushed, incomplete and hasn't changed enough to warrant charging £5 less than the last one for less than 1/2 of the original contents. Dont buy it, buy confrontation.
The few things I am willing to say in defence of the new rules is this; the new system will help gamers who haven't encountered 2nd edition 40k play Necromunda without having to find out what a sustained fire dice is, and how one would acquire one.
Also I do concede that that the gangs needed more diversity in weapons, but they have made it a little silly, and made some weapons (such as power swords) very difficult to acquire.
Confrontation, although I have never played it sounds very much like your average RPG system and believe me D100 systems are a little comlicated but probably because of GW D6 propaganda. Also the illusion that insinuates that the New Book is an improvement is also GW propaganda too.
I really hope GW does something to make the new game better and bring it back to it's former glory. If GW restore the rulebook to something resembling the size and diversity of information of the last edition then it will definitely surpass Confrontation in my eyes.