They're probably OK.
The main people that get in the promax levers are here, I think the one you linked to are short and the ones I linked to are long. Another option is one of the canterbury guys is making levers that looked really nice, think he was gonna charge £15 but can't remember, there's a thread in the main polo bit about them. Or buy a different cheap normal lever and attach your mod to it.
They're probably OK.
The main people that get in the promax levers are here, I think the one you linked to are short and the ones I linked to are long. Another option is one of the canterbury guys is making levers that looked really nice, think he was gonna charge £15 but can't remember, there's a thread in the main polo bit about them. Or buy a different cheap normal lever and attach your mod to it.