I've used both the HJ and TL 'twist to tighten' turnbuckles.
On the HJ it was turn until not loose and then with a finger nail, press against the housing and hook then turn until there was a 1/8" gap between your finger nail and the housing. (compress the spring)
On the TL there is a o-ring. When off/loose move the o-ring on the hook so that it is against the housing. Attach and turn until there is a 1/4" gap between the housing and the o-ring.
While I rarely (if ever) take my camper off my truck, it seems that ether system has a bunch of turning involved. I do find that the square housings on the TL are easier to tighen by hand and I'd always have to resort to using a wrench on the HJ ones.
- Mark0.