When I built my computer last year, the motherboard I picked out had two M.2 slots for ssd’s. At the time, I went with regular hard drives (though I had 2 hard drives at the time). Then a week and a half ago, I finally decided that I had run out of space on my main hard drive. So I ordered a bigger one (albeit slower). About a day later, I realized I could afford one, so I ordered a new boot drive (2 TB M.2 ssd). The hard drive arrived Saturday, the ssd arrived Monday. Tore the computer apart, and then I realized that the SSD didn’t come with any M.2 screws (they apparently exist). Fortunately, my tower came with a case of extra screws, and I found one that fits, and the motherboard already had the right riser installed in the proper slot). A drawback was that I had to remove my video card to install it (my experience is that if I have to remove a part, there’s a real chance it won’t get put back in properly). But I reassembled my tower, and everything was reinstalled properly.
My tower has enough slots to hold more than two hard drives, and my motherboard has enough SATA ports, too. The one catch was my power supply. I didn’t have enough power couplings. So I’m going with only two HDD’s (a 4 tb and 8 tb). Plus the 2 tb SSD. My ssd isn’t the fastest around. But it is so much faster. Last week, when I turned on my computer, it took at least 2 minutes to reach a desktop, and then it still took even longer to finish loading everything. Now it’s a fraction of the time.
If your motherboard can handle an M.2 ssd, I highly recommend one.