I have a sterling55, while I do like the cleaner sound, over the 57, It lacks that nice tubey, warm feel. Do you have any suggestions as to where I could find any microphone impulses for mics like AKG ? I really like the AKG 414, which I have used once, but don't really like the price. As far as preamps, They still remain just out of reach of my budget. Looks like impulses may *help* the situation a bit. Any ideas where I can find them?

There are mic impulses out there, though the ones i've come across have involved speakers and aren't very accurate. Perhaps they may be ok with some eq. Possibly the best option out there is the antares microphone modeler, this lets you inform the software which mic you are using, then you can choose the mic you wish to emulate.

that's what I told, but in an interpretation. It's not just about slew rate (how fast microphone is) but mainly it can be.