Bearings

[Will's]

So this weeks club nights I had a steering issue and one of the points we noticed was quite a bit of play in bearings ( currently running a Schumacher KF)?. So this has now got me thinking about bearings and I have the following questions,

1). How good are standard kit bearings?

2). Can you replace them with upgraded bearings?

3). What are the best type to replace them with?

4). General advice

Thanks everybody!