brotherhood_of_LAN - 1:33 pm on Jan 28, 2013 (gmt 0)
Depends what you're after tbh. If it's liberal usage in a high traffic environment I'd say the JS route works out better, anything client side at least.
I've tried flot but it seems incomplete compared to other packages, and I had some issues with axis labelling (iirc I wanted the labels tilted)
The last package I used was highcharts, which is JS driven. I visited their site just now and coincidentally they have an elaborate server side solution using a headless browser. hmm. PHP would seem simpler and more server friendly I would have thought.
fwiw they're all using <canvas> and SVG so a custom workaround may suit you.