I'm using the Joe P manual boost controller with some success. It costs something like $45 shipped brand new. Certainly not a fancy model, but seems to do the job well depending on what you need. You might check it out at http://www.boostcontroller.com
^^ using the same one. Works perfect; never had any spikes. Just make sure when you are working on your car and bump it, to double check the lock nut; as mine came loose and I didn't notice because a hose clamp stripped on my IC pipe so I was driving slow. I get home and the bolt/lock nut fell off!
Took me almost an hour to find the right size @ Lowes! If you ever lose it; here is what you need.