Western Digital WD Blue 500GB SATA3 3D NAND M.2 SSD for $88 each. Get free shipping for orders over $79.
The other places I have seen online are at least over $100 each.
I have an older MSI GE62-2QF gaming laptop with 3 x M.2 slots - 2 x SATA3 and 1 x PCIE 2.0/SATA3. I am getting 3 of these to replace the 2 x 128GB Toshiba SATA M.2 (RAID 1). This is my boot drive. Windows 10 is already bad enough but there are some programs that will only install on the boot drive and Program Files folder keeps getting bigger. Keeps getting the Low Disk Space warning. I can set all 3 M.2 Slots to RAID 0 since I am filling all 3 slots with the same capacity drives.
edit:
From WD Australia's website
https://shop.westerndigital.com/en-au/products/internal-driv…
5-Year Limited Warranty
Every WD Blue 3D NAND SATA SSD comes with a 5-year limited warranty, so you can be confident of your storage when you upgrade or replace any of your drives.
Not sure how they compare, but the Crucial MX500 500GB is currently $86.50 at Online Computer (I believe free shipping too)