My question is what is the reloading life of Lapau brass against a more inexpensive brand such as Remington or Winchester?
A lot will depend on how hot you load and what your practices are. The Lapau brass will be much more consistent out of the box. But if you take the time to prep and sort Remington or Winchester (assume a 20% yield loss), the lower cost brass can be just as consistent. After that they will yield equivalent accuracy.
How much do you set back the shoulder when you full length size? If you are setting back the shoulder 0.005", then any brand is going to experience short case life. If you neck size and just set the shoulder back when chambering becomes difficult, then any will yield lots of loads.
Do you turn necks? Do you uniform primer pockets? Do you remove flash hole burrs? Do you weigh cases and sort? Do you anneal necks? Do you neck size, and if yes, how? How hot are your loads? How do you lube and how uniform is your application? All of these and more will determine case life in # of loads.