i think the bb browser (or the blackberry as a whole?) is a lot more dependent on strong signal than some other phones. providing you have strong data signal you can pretty much evade the slowness problem by going to "cache operations" & emptying something. ofcourse you can try other browsers (i like bolt as it patches into youtube) but bb browser is more of a browser than a multimedia browser, if you get my drift.
these are all my findings so far & i'm only comparing to s60 v5 browser. yes it has a funny way of loading pages but i don't get frustrated with it in the least, mostly because i like the way it renders pages in column view (have you seen other browsers in column view? terrible!) & the download manager in bb browser is better than that in opera mini's, [imo].
i like the way it bridges the gap between default browsers & ad-hoc browsers like opera mini. but ofcourse, i can't wait for the webkit browser