Congratulations on the FW!!!
I would say the mint green is my favorite color for a FW and then the white would run a close second. It wasn't until the end of the 221's era that Singer started introducing the different colors. Funny thing about the white FW's they were the cheapest ones you could buy at the time, the budget model. They were lacking all of the decals and only had Singer on the arm. But even back in the day they were sold new they were almost a 1/4 of the average annual salary.
Maybe thats why they are fetching good prices now because few were sold.
Billy
Oh while I am thinking about it all of the lowshank feet/accessories fit the 221K, they do not have to be strictly for the FW. The 15, 66, 99, 221, 222K are all the same with the exception of maybe the darning plate I will have to check on that. But I know that my even the feet from my 1910 27 will fit the 221.
The reason I am saying this is you do not have to spend the extra money for the exact same thing just because the seller says 221 or FW. And that will let you spend more money on the important things like FABRIC!!!