Field recording gear

I don't usually write this kind of post, but I'm pretty excited about finally having a semi-professional field-recording setup. I'm now using a Marantz PMD671 with a pair of Sennheiser ME66/K6 shotgun mics in shockmounts with a stereo bar and a hand grip. (Beware of the kit, by the way, the shockmounts are NOT universal). I should say "will be using" as I haven't yet put this rig to the test. When I receive the backordered Gator broadcasting bag and the rechargable battery unit for the Marantz, I'll finally be ready for fully mobile, high-quality recordings.
I haven't been making too many so-called "field recordings" in recent years, largely because of my problems with the whole urban/rural dichotomy. Recordings made around the city are sure to include distracting automobile and airplanes sounds. Recordings in lightly rural or more wild areas get caught up in issues of "nature-ism" that I find equally distracting.
At the same time, I treat all of my recordings as "fields" - I have very rarely recorded in studios, and I'm always interested in the whole range of factors which might influence the acoustic character. The size of a room, the materials of the walls, the number of participants, the placement of the mics and sound source(s), the mediation of varying quality speakers or analogue distortions, and the choice of acoustic source itself, all influence the sound. That's why Shaeffer's solfege of musique conrete is an impossibility, as well as any comprehensive notation.

Anyway, I've briefly tested these new mics and I'm quite pleased. My next purchase will probably be a pair of ME62 omnidirectional capsules (the adaptability of the K6 series is pretty great). Eventually, I would love to own a pair of the Sennheiser MKH series, my dream mics at this point.
I'm wondering if anyone has thoughts on battery-powered mic pre-amps to complete this current rig. Are they necessary? Is there anything that might come close to the Sound Devices mixpre?