I'm looking at getting one, after reading the test i only need one for the odd job, and with the clarke showing a mild % error it isn't bad for the general job and that'll be a lot better than normal gauge of hand
I got one in the end: http://www.machinemart.co.uk/shop/product/details/cht204-38in-drive-reversible-torque-wre/path/ratchets-torque-wrenches-2 Got this Clarke CHT204 torque wrench from machine mart as its a small torque wrench, ideal for smaller bolts and came handy for my spark plugs as the big boys start from 28-30nm onward, so wanter more accuracy with the smaller torque levels. For 17 its great, ok I agree with the autoexpress comments on its bigger brother with the micrometer scale (as there're the same type) but overall with the reversal head and makes a nice solid click when reaches its torque setting.
ive got three a cheap on from screwfix, a teng 40-210nm, and a beta, 60nm?-300+ bought in that order, the screwfix one did lots of work,built a 2ltr 8 v, head gasket etc, engine still runs well didnt snap any bolts with it.. loads of stuff then i started abusing it and then got the teng. for the money it lasted ok but by the time the teng came it was out. cheap one 10% lower. the teng is spot on, and will go as low as 30nm, use it all the time just done HG with it etc got Lb/ft and nm on it got degrees on the head. beta one is badass not have enough use to comment on it properly yet!
I got my Teng calibrated at http://www.lambda-cal.co.uk/torque_calibration.php to be sure it's spot on every time.