Yes & No,
Yes, because if you get them to work they basically work, and you can have extra features that you can have with a bleed valve, stoping boost from spiking, making it spike, gear & rpm specific boost etc.
No, because they can be a pain in the rectum to set up properly and can take some time. - refering to the Apexi AVC-R.
If you'r after a decent controller that is only been new to the market go with the JayCar electronic boost controller - You can't go wrong for $150 with the digital read-out Hand Controller.
For more info on the JC controller view the Nissan Stagea section under Vehicle Specific Discussion.