I've always just plugged straight into the front of my amp.
I've recently started using a Digitech badmonkey in front of my evh iii stealth.
I like the way it sounds. Is it old age?
What are ye using for preamp boost these days?
My whole rig is cobbled up but ultimately I'm using a modded clone of a Fulltone Bass-Drive that I build (Richter) in front of my Laney Ironheart. I've the Laney set fairly low gain for cleans (3 or so) and the Richter for all heavy tones. Used a Moose Battlehammer for years before that which also sounded great.
I used to use a Tubescreamer for a while but went back to plugging straight into the amp, a Fryette Deliverance. I use the Billy Gibbons method, crank the living fuck out of the amp gain and use the volume control on the guitar to give me the amount of distortion I want.
Love the MXR micro amp for boosts. One knob...simple and does the job.