I've got a DX-398 that I use primarily for AM DXing, often while
traveling on business trips. With that in mind, I'm considering
replacing the stock 4.8khz IF filter with either the Kiwa
3.8 filter or the more expensive DSP filter modification from
WX3G.

Details on the DSP filter can be seen at:

http://home.earthlink.net/~wx3g/

Just wondering if anyone else has compared these two
options?

Greetings from Sactown, Bill E. Only 398 audio mod performed was replacing the
stock audio caps to increase fidelity. As a side benefit, f.m. stereo
soundstage via headphones & tape out has widened. Grundig's YB-400 f.m.
performance, though aurally impressive, now sounds "flat" in comparison. Also
substituted Sangean's stock speaker for one from a Sony 7600G. You might be
better served removing that mw attenuator, which will increase 160 metre ham
reception as well. Best of dx from sactown-n-WA6020SWL!!!