Thinking about a prepaid service plan for my out of warranty BMW

I’ve got a 2015 BMW X3 with about 140k km on it. The car has been reliable but I know things like the water pump, valve cover gasket, and transmission service are coming up. I usually pay as I go but I’ve been looking at prepaid service plans from independent shops. Some of them cover major items like belts, hoses, and even the water pump, not just oil changes. I found a place that offers Abu Dhabi Service Contracts Available and the price seems reasonable for a two year plan. My question is, do these plans actually save money or do they just give you peace of mind? I’m worried about fine print excluding things like labor rates or only covering certain hours. Has anyone here signed up for a service contract on an older BMW and actually come out ahead? Also wondering if they use genuine parts or aftermarket. The car is paid off and I plan to keep it for another three years. Any experiences would be great. Thanks.