"l did lower and stiffen the suspension at the same time and the caster/camber is slightly out, is this the problem."
In a word YES.
Bearings are what allows machinery to move freely & are made to tolerances that
are roughly 0.002"(2 thousandths of an inch) per inch diameter.
That is for an inch shaft that a bearing fits onto, that bearing will have 0.002"
tolerance(gap) between the bearing surface & the journal it moves on. Wear on
bearings is caused by that gap becoming bigger(slacker)/smaller(tighter).
Adjusting the parameters of a bearings intended conditions will cause this gap
to increase. Lack of oil will heat it's surfaces causing expansion & so will an
increased gap between surfaces.
I'd doubt VERY much that the bearing was a cheap one(is there such a thing?) as
it's the machining of the bearing during manufacture that costs the money not
so much the quality of the material so why would they use cheap materials(not
worth it for a company in the long run).
The code on the bearing itself will tell you all you need to know to buy a definite
top quality replacement. I found a quick reference to look up a bearing for it's
size rather than one to fit a particular car part, as buying for a particular
purpose means you've just been charged for someone selling you the CORRECT
one(according to them of course!) for your car. Meaning that £3 bearing has
cost you £8.50 because they knew the size(from the bearing code) & you didn't.
So here's how to source your own bearings correctly from the code & not just the
car parts shelf.
http://www.bearing-king.co.uk/" onclick="window.open(this.href);return false;
I'd reccommend SKF(SKEFCO) or NSK bearings & to get your tracking correctly adjusted.
Hope this helps.
My nearside one lasted less than 12mths and managed to seize itself to the hub. Right pig to get off - that was a JK one as well. Strangely the offside is fine 
Wherever you get them, get the good ones. 