I'm very happy with the way my stock PMD 671 performs in the field. I've used it with a w-mod UA-5 (coax in) and line in from my DAW. I'm especially impressed with the meters. They seem to be quite accurate and I am comfortable with the way they work.
I have my recorder set up, so when I turn it on, it is properly configured and ready to go. Fire it up, just push the record slider and away i go. I used an external battery pack to record RatDog recently. (
AA 2500 mAh Powersonic NiMH batteries. They recorded the whole three hours plus show with lots of room to spare. My Kingston 4 GB CF card worked flawlessly. I have noticed that the headphone output isn't very good, it's hardly able to drive the several sets of headphones I've tried with it. This isn't a big deal for me, but if you want to use headphones with this recorder, you should get a separate portable headphone amp.
Now, i just have to get it ACM moded before the Boulder ARU shows in January. I can't wait to use it with this modification!