Timely post. I just performed an "upgrade" to the Debrox system (which was recommended by my doctor). I picked up a better irrigation system - Nuance Medical EarClear Rx. There are quite a few offerings like this. And the pressure generated more closely approximates what my doctor performed.
I would caution you to have this done by a professional first, as the sensation of the stream flushing your ear is a bit odd (not painful). In this way, you can get a sense of an acceptable pressure to safely inject.
With the above spray pump, I approach it cautiously each time I use it. You never know when something like this can go out of spec ;-)
Note that for the Debrox system, there are several less expensive alternatives - especially if you don't want to wastefully purchase the "ear bulb" with each bottle of cleaner.
... Thom @ Galibier