A crankset using an external bottom bracket (what I *think* you're referring to when you say English) uses bearings with bigger seals, and therefore has more friction. This is because the bearings are more exposed, and need to be sealed better in order not to be compromised. You are getting a stiffer crankset and spindle, but that is the unfortunate price you have to pay -- it is the same from Raceface Cadence to Shimano Dura-Ace. The Raceface Cadence crank basically just needs to be tightened down really tight. (I think the instructions say "firmly" but it comes to the same thing) If you like torque wrenches then around 35-50 Nm.

One thing to look out for on older bike frames is that the sides of the bottom bracket need to be faced and the threads inside need to be chased before installing an external type bottom bracket. This is because with a square taper bottom bracket, the relation of the bearings to one another functions independently of the accuracy of the threading of the BB -- everything is just pressed onto the BB spindle. However, with an external bottom bracket, the two cups screw on separately, and if they aren't perfectly parallel, they will wear out really fast, leading to people who didn't do this complaining on the internet about how quickly that type of BB wears out.