I'm working on a plugin and testing the performance of some of the ways we do things and for some operations it really seems like there's a big difference depending on which browser you use.

If I optimize for slower browsers that means that the majority of users who are on faster browsers will use a slightly slower version - so that users in the older browsers can have a slightly better experience. The overall experience here is less good, but more unified from browser to browser.

If I optimize for faster browsers that means that the majority of users who are on faster browsers will use a slightly faster version - and users in slower browsers will have an even slower experience. The overall experience is that it's better in fast browsers and less good in slower browsers.

I'm stuck, which is better to optimize for - and why? Should I keep the experience less-good in some browsers but more consistent in all, or better for most users at the expense of slower browsers?