V9's And V10's Has Anyone Found Out!!

[psxmodsuk]

Hi all has anybody found out why some v9's and v10's fu*k up and others dont ? is it a fault on sonys behalf or is it what discs you use ?.
My mate was telling me that sony have told shops to just swap v9's no questions asked if anybody takes a nack'd one back to swap it for a v10 so that points the finger at them yet ive also been told of v10's going down for no reason.
I know theres posts on the forum saying that if you use certain dvdr media it can screw up the lazer diode i always stick to ritek media myself and havent had any problems really but i havent chipped that many v9's and v10's.
So dose anybody think sony have done something to the consoles to detect certain mod chips or could it just be poor designs as it dose state the v9's and 10's are more compat with dvdr media so surely you should be able to use any brand of disc , please post your findings as i would really like to get to the bottom of this problem as its making me not keen on chipping them for ppl.
Regards