I was struggling with this same decision on whether to purchase the exact same Explorer 114270 and the Grand Seiko SBGM221. Ultimately, I went with the Explorer. While I still want the Grand Seiko, maybe not specifically the SBGM221, I went with the Explorer bc I felt like it was more timeless and has more history. My obsession with GS is new, and grew intensely and rapidly, and ultimately I feared it might fizzle out in a similar fashion.
That said fully intend to add a GS of some sort in the future.