I suspect you searched Google and found conflicting views on bending similar heating elements. Unfortunately, most of those views are not supported by anythng more than opinion, and certainly not by any information from the manufacturers.
Watrod is one such manufacturer. Here is what it has to say (
https://www.watlow.com/downloads/en/specsheets/hanwat0713.pdf ):
Here's a YouTube (not from Watrod):
Another question that arises is the effect of previous use on bendability. Again, there are conflicting opinions. It is also harder to find comments from the manufacturers related to that. Unless the internal filler somehow solidifies during use -- another unsubstantiated claim made on various blogs -- I don't see how the normal use of something to heat water would adversely affect the temper of the steel sheath. Whether higher temperatures (say dull red) will lead to better or worse temper depends on what metal is used for the sheath. That is something that is easily found, once you determine the specific heater you plan to use. What you want to avoid is bending a bend. That is, the first bend will work harden the sheath. When you try to bend it again, it will not bend in that same manner as it did before, and the work-hardened metal may crack.
There are "bendable" heating elements. McMaster-Carr sells them, as do other suppliers. McMaster is a little more expensive, as usual, but it ships quickly and at least you know what you are getting.
Based on those observations, I think the device you show from HD may not be suitable to additional
severe bending: 1) It has already been severely bent; and 2) It is single-ended. You have not said how much bending you need to do. Since the price is quite reasonable, this may be a case, though, where experimentation is the easiest and most cost-effective answer. If it is more than just gentle, then I would look for a double-ended heater or a heater sold as "bendable." Check the web site of whatever brand/manufacturer you use for its recommendations.
Finally, as you know, when you bend tubing it tends to collapse. That will compress the filler in the tube and may lead to hot spots, if supports for the internal heating element are not designed for such bending (See: technical papers on the Watrod site). I would suggest using a tubing bender that supports the tubing sides and reduces such collapse, particularly if you are bending more than , say, 30 to 45° or the bend radius is small.
John