I had a bleed valve then switched to a cheap manual boost controller- the difference is like night and day- the manual boost controller hardly spiked at all and held the psi much better.
big difference in the way they operate- you wann make sure its the ball and spring type not the simple screw in and out bleed valve.
I think a few of you missed the point aswell- he was asking about
A MANUAL boost controller vs A bleed valve not a relatively expensive electronic unit.