Anyone got one of these? They seem to be a lot cheaper than the others,
and I'm wondering if there's a reason for that.

http://www.heatingcontrolsonline.co....&reviews_id=12

Looking to use it with this boiler

http://www.saunier-duval.co.uk/manua...-23e-SB23e.pdf

The instructions look simple enough (page 25) but the boiler has a built
in timer already which I guess is wired the same way as an external
control, and can simply be disconnected.
Thanks for any advice