there is also a box to sort out noisey abs signals at £95+vat to factor in too....
I'm sure I remember seeing somewhere how to make this. There's only pennies worth of electronics in it. That saves you over £100 straight off.
I am the chap who developed this device and published the results including a proper software setup of the ECU on my website www.lotus116.de. Took me weeks(!) to sort out how to cope with the noisy ABS signals you get if you connect the RL ECU to it. I also developed a printed circuit board by myself and let them be fabricated (that costs some money, pal!), I made a housing, cable trees and built some of these devices in OEM quality. Sold a small batch of them for 50 euros per unit. I think that's been fair for all the work I put into it. The electronic parts built into the device are worth pennies, right. But there are some other things you have to take into account also. If I hadn't done all the work noone including me would have got the opportunity to fix the noise issues at very low speeds.
If I read comments like this it does not emphasize me to publish any other important results I got from my work.
Note: if these devices have been sold for 95 pounds + vat someone has made some profit reselling them. But profit also is not bad. It's necessary to keep the ones live their lives that deliver you the goods you need.
And I would bet a fortune on, that every one of you earn your money by things someone developed who has to be paid for and the profit others make by fabricating and selling these things.
Just think about that for a minute!