This write up applies specifically to the BC1200 but there's o reason to suspect that others in the range are any less good...

These computers are excellent, I've got four of them on various bikes, all with the wireless transmission kit. I switched to Sigma from Cateye a few years ago because the cateye brackets were, quite honestly, crap - the head unit was always falling off, the last straw was when I lost a computer in a dark lane at night.... No such problems with the Sigma, the twist-lock mounting for the head unit is super secure.

Fitting the sensors/transmitter is dead simple - they're held on with rubber o-rings so its easy to get them on oversize handlebars or deep section aero forks. The transmitter is nice and small too unlike some which seem to have Jodrell Bank as a close relatives... I've never had a problem with reliability through all weathers and the batteries (CR2032) seem to last an exceptionally long time... one of my units hasn't had a new battery in over 2 years and has 25,000km on the odometer. The only fault, if it is one, I've found so far is that my Solo-Logic lights interfere with the transmitter... not really a big deal, my winter training hack has a wired fitting kit now to get around that problem. Of course if you don't have the same lights on your bike then you probably won't have a problem.

The BC1200 has all the functions you might want except cadence (you need the BC1600 for that). In 2006 Sigma face-lifted their range of computers so they're now have designations like BC1106, 1206, 1606 etc etc. There's no reason to suspect they're not as good as this one.

There is one downside to it though... the battery might last ages but when it does expire the fork transmitter battery is fiddly to change... you'll need a proper jewellers screwdriver to remove the tiny screws holding the backplate on, one of those mini screwdrivers you got ina christmas cracker just won't cut it! The receiver and head unit batteries are easy however, just a twist-to remove battery cover.