striaght cut gears dont have syncrhos (a normal box has synchros except for reverse, hence the whine in reverse) and straight cut gears are the type of gears in the gearboxes referred as 'dog boxes'. the os giken gears are a 'cross mission' gear that uses synchro's, so they are still very streetable and have a good life span.
so in other words, if its a race dedicated car with a decent amount of power then get a dog box, if its driven on the street also, get a box with synchros (i've also heard ppg are bringing/have brung out a gear set that uses synchros also, not entirely sure though)
bite me b!tch