Well - I have three sorts of thigh pads.
Firstly have a BAS outer thigh pad which offers absolutely superb protection as low cost - got the pad from Asad and would totally recommend it for protection.
Then has Aero P2 pads which offer pretty decent protection and comfort. Prefer the P2's over the P1's as they are less bulky. I remover the hip cup.
Then more recently I have custom Stratton Fox pads which are as good as it gets!! The pretection and comfort is crazy!
So depends on budget really! If low budget then the BAS should be as much as you'd ever need protection wise!
For low-medium budget then the P2's are decent value.
And high end the Fox's are off the scale!