Well, after I finally figured out the liberators are just to be glued on to the ends of the driver side of the cup, I caulked (read: hot glue) the liberators in and gave it a go. Setup was MS1+Comfies (no mod), SOHAII, and Auzentech Prelude. Initial impressions: With this setup, you lost a little bit of the electric guitar sharpness in busier passages of songs, but still sounds 100% Grado in solos. Highs are also tamed slightly compared to before, and as my friend, a HD650 user, noted, less harsh. Personally, I never found the MS1 harsh and now find the highs can be dull at times with no sharpness or ring. This probably comes from listening to A700s all the time, where the highs are boosted but never harsh. But for those small downsides, you do get some big plusses. Bass has come out stronger, deeper, and with more impact. Soundstage, the big one, increases to the point where the headphone is no longer annoying to wear, personally. Before, the condensed soundstage of the Grado annoyed me incredibly, considering I normally listen to the A700s wide(r) soundstage. For the most part, the Grado sound is preserved, but with more bass and soundstage. If I were to quarter mod the comfies (not happening) I think I would get the highs back, and possibly the guitar mids as well. I hope that the HD414 pads will come in soon and show at least some improvement over the comfies. I can't get my hands on Grado's bagel pads ($45+shipping? No.), unless somebody here knows a local with a pair.
Another advantage is that comfort has actually increased. Because the headband is forced into a different shape, the pressure ends up being placed between your ear and temple, instead of on the back edge of your ear which tends to get sore after an hour or so.
I'd also like to note that the MS1 sounds like ass out of my D2 Boa, both before and after the mod. The highs were pretty muted before, and now with the liberators, is totally lacking. I'll be doing further testing via ALC885 (onboard) or directly out of my y1.
I'll do more listening later, including changing the porthole plugs and pads.