Yeh, hes done well.
I just need to get some custom injectors calibrated then my hardware will be in place, I'll then have another crack at it. I've been using the Arduino for well over a year, nearly 2 in fact and it has been completely reliable so can recommend from that point of view. They are also dirt cheap to make and you will always know exactly what to do should ever it need replacing. There are some tweaks to the hardware which are required to make it work in our Rovers but it is all well documented on .org as I'm sure you've seen.
I think getting the right turbo is key and fro the sounds of it, the turbo he has used is far from off the shelf so not sure how willing he will be to tell people the exact specs.
If you decide to go down the Laguna 1852v route then obviously I'll offer any help I can, loads for you to see in my build thread about how I did adaptor plates and clocked it slightly though if youre interested
. Probably not the ultimate solution for power but I think it will do well and is a relatively straight forward fit as it is orientated almost perfectly from stock so no moving actuators etc is required, it doesnt even need to be clocked really, it was just a little extra I did to help the oil flow through it.
Have you got a short list of turbos yet?