Have run link plus, was a nightmare -driveability, tuning, fuel consumption all terrible. Spent countless hours on the dyno but couldnt fix niggling problems like starting (hot or cold), nasty hesitation coming onto throttle etc. I initially chose due to the impressive feature list
Currently using PowerFC, besides the handcontroller being a pain in the arse to read in anything but perfect light its has performed well, cheap to tune (with plenty of options when it comes to tuners as well). Definantly better featured ecu's around in terms of features (launch control etc) but its hard to beat thanks to price and ease of use.
Personal experience with the ems on mates car is its a very good thing, driveability, fuel consumption cold and hot start all on par with the pfc in my car. Unfortunately some outputs on the ecu arent functional as claimed in the specs (8860) although ems assure they will shortly be available with a software update (which the ecu needs to be sent to ems for).
Autronic gets the vote