That's always enough, doesn't even have to be expensive oil; Inexpensive products are also perfectly fine. Second-hand refined oil is not as bad in terms of quality as it is reputed, but you hardly save anything, especially if you choose no-name oil from an accessory or hardware store.
Expensive synthetic oil brings nothing into the coffers except the workshop. Years ago, Mercedes tried to explain to me the sense of 5W-30 for the old W202 from 1997 ------> they only let it go when I explained what to understand about cars and insisted that there was one 10W-40 comes in and the M111 engine has wide oil ducts, 5W-30 or even 0W-30 makes no sense here. Then the mechanic also meekly indicated that my argument actually makes sense, but he had the "order" to offer it to people. With me he came across a customer who knows his way around and then got 10W-40. Then the branch earned less, but that's not the customer's problem.
Most workshops try to sell expensive oil by saying that 10W-40 can only be used in tractors or riding lawn mowers, but that's nonsense; it's all about the money and one hopes for unsuspecting drivers who can be withdrawn.
In the end, the valves or hydros rattle because the oil is too thin, that doesn't help and often there is also high oil consumption; my old Omega-B 3.2 V6 from 2003 had also received 5W-30 from Opel and became an unrestrained oil eater before 10W-40 brought improvement and never had to be refilled between the intervals. And the E46 is also one of the cars that came out when 10W-40 was standard and there was still no 0W-30.
No, 10W-40 is okay and it should be left at that as well.