Is one of these better than the other?
Which one should i use?

http://www.aemelectronics.com/product_info.php?cPath=14&products_id=655

http://www.aemelectronics.com/product_info.php?cPath=14&products_id=662

are you going to run more than or close to 3 Bar? if not save a $100

sounds good to me

you can get a nice one from here:

http://www.roadraceengineering.com/ems.htm

kav-3bar is the part number. It is a higher quality unit than the AEM one and it is cheaper (comes with harness)

Brent