I'm running Excel takasago on my crf450r. You can lace them right to your OEM hubs which will save you some money.
They are well worth the extra money. You really can't go wrong with them.
oh... I'm running a 5" rear with a 160 Pirelli Diablo and also converted the rims to tubeless ( well worth the mod btw ). If you go with the 5" rear, you'll have to dish the rim right to clear the chain.