original tailgate struts are the way to go.

i've seen an number of gas mods done with off the shelf struts and holden other parts (such as the wagon struts) but i've never seen anyone get the tailgate to sit in the same angle when open.

with the tailtent the only issue with gas struts that hold the tailgate open higher than standard is that the tailtent might be stretched and you might stuff the door zipper. if its open less than standard then the tailtent may keep slipping off as going by what i saw on goats tent the tailgate corners are used to hold the tent up.

the only reason your 'standard' struts slam the door shut when going over bumps or that you are continually having to manually lock the struts open is because the retainer spring has either broken or fallen out. i searched for years to find good struts that had the original springs so that when i open my tailgate i push it fully open and the thumb tabs automatically flick out and lock the tailgate open, the springs also keep the thumb tabs in position when going over bumps.

yes it would be nice to not have so much noise on bumpy roads and be able to just close the tailgate without having to unlatch the struts, but at the end of the day its your own choice.