I imagine the difference is so small that it's not even worth considering if you have one and a better trinket from SoO. If you have both then I'd probably stick with HLG, especially if you prefer the 13153 Haste Breakpoint.
HLG heroic is much much better. I wouldn't say the manareg from HLG is twice as much as from Chi-Ji, but it's a lot more, especially with a high haste build.
Horridon's is one of the few RPPM trinkets that the proc rate still scales with haste. With the 13k haste build, the 510 version was regen-ing more mana than my innervates were at the time (prolly 12k ish spirit back then). So a 543 is definitely gonna smash a Chi-Ji