Hi Fernando,
I don’t really think that I have a clear answer and I want your opinion.
I installed an Samsung M.2 960 512GB Pro on my Asus Z270A. I also have a Samsung 860 SSD 512GB. I set my M.2 on M.2_1 slot and settings at PCIE mode. My drive is split in 2.
Although Crystal mark shows some impressive benches VS the Samsung SSD, I must say that I t really doesn’t boot faster. In fact it boots slower than my 14 inch laptop ROG G46VW which has 2 ssd’s.
I have the version 3 Samsung drivers for the m.2.
1. So, my question, am I doing something wrong, or is the performance just not noticeable (especially on boot)?
2. My other question, am I blind, I don’t see version 16 of AHCI/RAID drivers on your recommended section.
Thanks. 
EDIT by Fernando: Thread title corrected (original title was “Samsung M.2 960 Pro VS Samsung 960 Pro SSD”)
Performance and boot time are different things and depend on different objects. An NVMe SSD usually has a much better performance than any SSD, which is connected to any SATA port, but not automaticly a shorter boot time.
The boot time depends on the mainboard, the BIOS and the sort/amount/configuration of the attached HDDs/SSDs.
I only can recommend drivers, which gave me very good results while having tested them.
According to my recently done benchmark comparison tests with my Z170 chipset system other (older) Intel AHCI/RAID drivers are better than the currently available Intel RST v16 platform drivers. Since none of them are already fully developed by Intel, this evaluation may change in the near future.
Nevertheless it is possible, that the latest v16 platform RS drivers are the best choice for Intel 200-/300-Series and X299 Chipsets, but I cannot recommend them, because I haven’t such test configuration.