mine was also lots of stright driving. thing is, with so many traffic lights and speed changes that you mentioned, cound the time where you are at a speed and not accelerating or braking from the lights or to dodge cars, or for roundabouts etc etc
the time when you are cruising at speed is minimal
you would end up activating the cruise about 10-15 times in a trip... clearly not worth it i think
also, they allow you to 'relax' more behind the wheel, making your rection times absolutely shithouse
but i'm not going to say anymroe as its your money and if you have your heart set on it then fair enough
in that case, i say check out autobarn or supercheap - they probably have some generic kits that are pretty plug-and-play type of things...
best of luck,
Warren.