My very first socks were large, worsted weight and knit based on this awesome tutorial from Staci Perry (she has, by far, some of THE best tutorial videos). This was my first introduction to the heel flap and gusset.
For my next two pairs, I went to smaller needles and sock weight yarn but stuck with the heel flap and gusset using Susan B. Anderson's tutorial for stitch counts.
Wanting to change it up a bit, I then tried an afterthought heel. I researched it a bit and found this fantastic post which provided excellent guidance and instructions on adding lifelines to make adding the heel easier. The heel didn't look as nice as the standard heel flap and gusset so I'm not completely sold on this one just yet.
I also misjudged the sizing and these socks were quite large...they fit my husbands size 10 rather than my size 8. If I use this heel in the future I'll have to adjust my "sock before adding the heel" length.
My current in-progress sock has an intriguing "strong" heel. This heel doesn't require picking up stitches and reminds me a lot of the thumb gusset in mittens. The heel is increased forming a gusset, then you turn the heel and rejoin, continuing on in the round. It is the most convenient of heels so far.
As I enjoy knitting mittens, the paired increases were familiar too. The only thing I don't like is the tiny hole when you begin working in the round after the heel turn. It's small, but annoying (you can see it in the picture below in the skinny brown coloured row that comes across the heel). I did try picking up the stitch between but its not ideal. I'll have to work on that.
I might take a small sock making break when this pair is finished but I think the strong heel may be my go to from now on. I may experiment with adding slipped stitches in the heel gusset (similar to a heel flap) to strengthen it...I'll keep you posted :)