The best thing about IPV imo is you can upgrade the firmware when there's updates. Example: IPV4 was 100watts, became 120watts and added titanium wire to TC options. IPV3 LI went from 165watts to 200watts. IPV3 LI has a nice solid case simple and clean inside much like the original sigelei 150w. Pretty much the same 510, and chip maker. The battery sled/case are slightly different.
In the end even tho I have 3 devices with TC I don't use it, I've became my own TC control and can tell based off flavor and vapor production. When something is going dry, I think in the last 5months or so I've had 1 dry hit and was because i vaped a rda low put it down to redrip it before using it but, but got occupied with something else and picked it back up and got a dry hit.