Read all previous posts. If you still want a pair:
Do win do many pairs below £100. Adidas powerlift 2s go for £70-80, adidas power perfect 2s (if you can find any, they're discontinued) will set you back £80-100. Several members of the forum have these (myself included).
Inov8 do their fast lift 335s for just over £100.
You could also take a look at the Reebok crossfit lifters, but I don't know much about them, I think they're less sturdy for squatting as they're designed for wods.
I see no point in going for adipowers or Nike romaleos unless you're doing Olympic weightlifting. For squatting only, the others will be sufficient.
Its worth taking a look on eBay. You can occasionally find an absolute bargain - especially if you have huge feet (size 12+).