Why do you want to upgrade your front brakes? Stock OEM SE-R brakes are fine for most street applications. The main reason to upgrade to NX2000 brakes or beyond is to avoid fade. Are you getting fade with your current brakes on the street?
If you have plans to do lapping days or turbo your engine, then upgrade your brakes. Otherwise, I would think that you would be better off getting new stock rotors and some good pads.
Here are some things I have learned about SE-R brakes in the last 10 years:
1. Your tires are the controlling factor in stopping your car, not your brakes, unless and until you get brake fade. You can lock your wheels now with your stock brakes. You are probably not going to make your car stop faster on the street by spending money to upgrade your brakes.
2. Stock SE-R brakes are all I need for the street. I have never experienced fade with stock brakes on the street. NX2000 rotors add several pounds of rotating mass to each of the front wheels -- not something that you want to do if fast acceleration is something that you seek. We pay hundreds of dollars to buy light wheels, why would we add pounds of rotating mass by selecting larger rotors unless we absolutely need them?
3. Stock SE-R brakes are not adequate for track use, no matter what pads you use. The NX2000 brakes with track pads are all I need for the track for my SR20VE. If you drive a turbo on the track, you may need more brakes.
3. Nissan OEM pads stop the car well and provide good long service on the street. They produce little dust. After market performance pads provide a higher coefficient of friction so your brakes feel like they are more capable (remember, all brakes are limited by the tires) but also produce more dust. If you choose the extra coefficient of friction, you will be cleaning your wheels every few days or driving with dusty wheels.
4. SS brake lines are OK, but most people really cannot feel the difference between SS lines and OEM lines in good condition. SS lines are subject to fraying and make it harder to move the calipers for pad swaps. They may be difficult to attach to the struts, requiring some special attention.
These are my opinions based on my experience. When it comes to brakes, as most things with cars, everything is a trade off.