From what info I can gather, Castrol Edge USA and Castrol Edge UK (the link the OP provided) are different base stocks:
Edge USA MSD:
Castrol Edge 5W-30 - US
Edge UK SDS:
Castrol Edge 5W-30 - UK
For a straight comparison, both safety sheets are for the 5W-30 version. Note that US Edge MSD lists composition as "Base oil - Highly refined - 90-95%". This leads me to believe that the US version of this oil is much the same as most other "synthetics" sold in the US...base stock = Grp III hydrocracked dino oil.
The UK SDS lists composition as "Synthetic base stock. Chemically modified base oil. Proprietary performance additives." Likely a Grp IV PAO similar to the German Castrol sold here in the US. This product replaces Castrol RS.
FYI - German Castrol 0W-30 is a Grp IV PAO base stock.
The Edge product is fairly new here in the US and has been hyped pretty hard with the "Think with your dipstick" commericals on TV. Castrol is taking direct aim at Mobil 1 (another Grp III oil) by saying it has "8X better wear protection than Mobil 1". Of course, this is using Castrol testing. User oil analysis will tell the real story...right now there are slim-to-none of those available. The only ones I could come up with are from the UK and Australia and are not valid due to the differences in base stock.
Castrol Edge is only available in 5W-30 and 10W-30 grades in the US for now. Here is the data sheet for Edge US.
Castrol Edge Data Sheet
This oil is fairly thin for a 30W multigrade...both the 5W and 10W-30 have a viscosity of 9.8 cst at an ops temp of 100 deg C. That is getting toward the bottom of the range for a 30W. Both have excellent cold start viscosities of 54.2 cst and 60.5 cst respectively. That is not surprising considering how the oil thins as it gets up to ops temp. In a 7M or JZ series motor, you may hear more pronounced valve train noise with this oil due to it's relatively thin ops temp viscosity...I experienced it using Amsoil 2000 0W-30 oil (also relatively thin at ops temp). You'll have to try it and see. Based on pricing I've seen, it sells at a premium compared to other Grp III oils available...i.e. Mobil 1 and Pennzoil Platinum. Is it worth it? Not enough data to answer that question just yet.
To the OP: Read the Motor Oil 101 link in my sig for info concerning what weight oil to use. The cliffs version: For 90% of the motors you want the lowest 1st number and a "30" 2nd number...i.e a 0W or 5W-30 oil. There are additional threads on this in the Lube section. My choice for Castrol Edge would be the 5W-30 version. Basically the same viscosity as the 10W-30, but a lower cold start viscosity.
I moved this to the proper section for further discussion.
