I finally got around to writing up a few things. Got my HighFive e-nail in! I love the graphic! I got pillars of creation and it is some very clever artwork! The red plane PID isn't very attractive IMO. The Omron obviously looks way better but is also more expensive. I wish I could change the red on the HighFive PID to white or blue or green. Oh well, it's not the end of the world
Anyways, the 710 whip ceramic nails do not fit with the Gimido or HighFive e-nail flat coils from my experience. I have both the 710 ceramic nails with and without the slit (I believe the newest design is the one with the slit), and both seem to be the exact same size. Unless 710 whip changed the design since early 2015 (when in purchased these nails IIRC), I think the threads right under the dish are just too large to fit through for most flat coils. Neither nails fit either flat coil I have. Here are some pics. The Gimido center hole is slightly smaller than the HighFive.
Gimido coil on top, HighFive on bottom.
Gimido coil
HighFive coil
My Gimido e-nail has the Omron LCD PID and the HighFive has the standard cheap red PID.
I still need to make some rosin and dab to see temp drop difference, but so far I was able to compare heat up times.
I set both e-nails to 680F. The Gimido steadily increased to 680F and it never went over 680F. The HighFive increased at a quicker rate and went to about 700F (the Gimido was at about 600F at this time). The HighFive then dropped down to 680F at about the same time the Gimido reached 680F.
So heat up time is about the same. Obviously the Omron PID is much more accurate since it did not overshoot the set temp. I'm sure the Omron will have less temp drop during hits, but honestly, if you don't glob, I think the cheap standard PIDs work very well
Also, one last note, the Omron PID sits at 680F and never fluctuates when not in use (okay maybe I shouldn't say never because I have seen it drop down to 679F before - probably from an air draft - but anyways it basically always sits at the set temp). However the HighFive fluctuates between 678-682F. Just helps show the accuracy of the Omron PID once again.
EDIT:
Made some rosin. Took small dabs on each nail. Maybe 0.02g size dabs. Both dropped down to 675F. I'm guessing this temp drop is more from the 70F cold carb cab and not the dab since temp only starts to drop after I cap the nail.
In conclusion, cheap e-nails seem to work just as fine for me as more expensive e-nails.
Hope this helps
EDIT 2:
I realized Quartz doesn't hold its heat as well as SiC so comparing the Quartz halo on the Gimido to the SiC on the HighFive isn't very accurate. I bet if I swap the 2 I would get an even more stable Gimido and a less stable HighFive.