technically, anything over 55 watt is illegal to use on the highway. those kc's (round) ones are for off road use only. the hella's (550 and 500) are legal for on road use.
but certain hella's (3000/4000..) are for off road use only..kc also has some lights made for on road use: 5x7 series/ 2x6 series... I'm not sure about PIAA lights as i jave never looked into them (sorry) also, many manufacturers will put the words "Legal in all 50 states, including canada" on the box to let you know they are street legal.
or, if your still not sure what to do, ask a pro at a truck accessory dealer.
2001 Ranger Edge Supercab 4X4 4.0L with 4.10's (8.8 axle)