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90% along the key emission line! Got to be happy with that. I'd seriously doubt you'd notice a difference. Keep in mind, there maybe some discrepancies in the spectral tests he performed or indeed, that is the filters true response.
While its nice to think that every filter is the same, they are not. This is the reason why the likes of Custom Scientific provide you with your individual filter's spectral analysis. Difference between them are typically minor. The shorter your bandpass, the more complex the filters are to make and subsequently cost more. You only need to look at the solar ha filters to get this into perspective. They have a very narrow bandpass.
Just keep in mind your overall filter goals. While you have a OSC now, you may go mono later. To save you the hassles you may want to select one manufacturer and stick with them. Manufactures don't all use the same thickness glass for filters thus if you use different manufactures it is almost guaranteed that they wont be parfocal. So if you think you'll eventually end up with heading the Astromomik, Astrodon, Custom Scientific, etc stick to one manufacturer.
There is of course a twist (just a warning). Even filters manufactured by the same company aren't always parfocal. For instance, my Custom Scientific LRGB filter set isn't parfocal with the Custom Scientific 10nm Ha filter. A focus change of approx 30 steps is required to hit the CFZ again. Some people are "hell-bent" on ensuring their filters are parfocal as it makes things a little simpler. But seriously, its not as big an issue as people make it out to be. It makes very little difference with automated focusing. You can also configure filter offset lists in MaximDL so that when a specific filter is requested, MaximDL tells the focuser to shift x steps to reach focus. Parfocal LRGB sets are probably more critical, not Ha - its just a nice to have imho.
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