I dont remember the exact amount these glyphs give but the difference between the CR150 recovery glyphs which requires the Jehade potency and the CR160 glyph that requires the Repora potency rune is literally 1 (one) extra point of regen, at purple and gold qualitys.

Example, a purple quality CR150 (Superb) glyph of stamina/magicka recovery gives I think 157 stamina/magicka recovery. While the purple CR160 (Truly superb) glyph of stamina/magicka recovery gives 158. The same for gold quality except I think its 167-168 from CR150-CR160.

Its the same difference when you compare gold and purple qualitys of the same level, so for example here:
purple quality CR150 (Superb) glyph of stamina/magicka recovery gives 158 while the gold gives 159. Same for CR160 except its like 168-169.

So please dont quote the exact values from me here they are close as I can remember but the point is..

TL;DR

You basically get absolutely no benefit from using your Reporas and Kutas on recovery glyphs as opposed to using the MUCH cheaper Rejeras and Rekutas to make a glyph 10 CR ranks lower.

Im sure this has been noticed by many already and this topic probably already has a few posts. Has anyone tested these out to determine if its a visual bug with the tooltip? It seems ludicrous that ZOS could simply overlook this, I mean gold quality items are what motivate me to get to endgame. Im not saying this is totally gamebreaking but Id definitely like to see a reasonable difference between gold and purple/ CR160/CR150 glyphs.