I've used the Rem oil & the hoppes. Both work fine. I am not familar with the
4D40, but if you mean WD-40, I don't use it. The spray can be too much in the receiver, it goes everywhere and make a mess.
I use Break-free to clean the gun on the outside, and then I lube it inside with remoil.
I use a bore-snake and remoil to clean the barrel...works great