I always write my Js with the bar across the top.
Even though you didn’t ask for it, here is all of the little details of my handwriting, see if you can relate/compare:
(warning: the following will probably be the most pointless rambling you’ve read in a long time. I’ve got too much free time.)
A: My capitol As are pointy, not round, and my lowercase As are the “non-typewriter” kind. ie:
___ . _____
/ I ____\
| | instead of / |
\___I. \____|.
E: I write it with the middle bar shorter than the other two. I think most people do that.
F: Same.
G: My lowercase g is also the “non-typewriter” kind. ie:
___ . ___ .
/ I / I
| | instead of \___|
\___| /__
| (___)
\___/
I: I almost always cross capitol Is.
J: See above.
L: My lowercase Ls are just vertical lines, not like the way they are typed with the little things on the top & bottom that make them look like a 1.
O: a circle. 
Q: I almost never write in cursive, but I just write my Qs as a circle with a 45° slash through the bottom right side.
R: The bottom “leg” thing comes from the middle, not the left side.
T: My lowercase t has the little curve on the bottom, which is “normal,” but some people just put a cross.
Y: My Ys are funny. The top looks like a squished U (not V), and then it has a line under it.
1: I never write the number 1 as just a line. It always has the underscore and, uh, little flag thingy. It takes a long time to write.
3:
I do it as _ rather than __
_) _/
_) _)
4: I do the “non-typewriter” 4:
| | /|
|-+- instead of /-+-
| |
5: I didn’t do it before, but now I always do it the way they tell you to in school, with the bottom part first and then the top line last. I don’t know why.
7: I don’t cross my 7s. The whole reason people invented the crossed 7 is because it looked too much like a 1, but if you underline the number 1, then you don’t need to cross 7s, and crossing 7s just makes it look more like a 1.
9: I do a counterclockwise circle and then do a diagonal line, rather than a clockwise spiral. Don’t know where I picked that habit up, but it’s the way I’ve always done it.
Wow. I never knew I could write so much, just about my own handwriting. I can’t believe I just wrote almost 2 pages! I feel like such a nerd. Don’t I have anything better to do? I’m wasting my childhood! AHHHHHHHHH!!!
::returns from looking at the preview::
Damn, for some reason, it skips a line whenever I use [ code ].