Minds are either made up one at a time by personal experience, or swayed in larger numbers by the public expression of those experiences by a few. I will point out to any Tascam reps who may be following this thread that it may be advantageous to consider the way in which these support issues are handled as an excellent, targeted, long term marketing opportunity within this small but influential community.
Opinions once formed are difficult to change. Minds are still being made up right now, and Tascam has the opportunity to sway the collective mindset in a positive direction by not even going the extra yard, but simply doing what is expected. The cost of targeting the opinions of a strong return-customer user base are few, but those are dollars well spent and the effects long lasting. Consider the poor reputation M-Audio became branded with and is still saddled by, 6 years after the rushed release and lackluster support of the Microtracker.
Fortunately I haven't had to deal with repair support for any my Tascam decks. I like the design, functionality, and price point of these recorders so I use them and have recommended them, yet I'm waiting to hear how more of the DR-680 problems are handled which may figure in reassessing my opinion. I hope the problems can be resolved. I did return a new DR2d that arrived DOA but that was handled without a problem by B&H. My DR680 and the other DR2d is working fine.
The only time I've dealt with Roland/Edirol support was for a broken input jack on the original R-09 about 5 years ago- I emailed them about it but didn't have a chance to send it in until 4-5 months later when it was fully out of warranty and they still replaced the board (and installed a new front case face) at no charge. Based solely on that singular experience, my dealings with Edirol have been excellent. I've bought several of their newer recorders since. Besides the good support I received, I like using their products so I keep an eye on their future gear and have no problems recommending them.
Others have had other experiences. Of course no manufacturer can always please everyone, but making an effort to get it right at an important moment when enthusiasm for a ground breaking product like the DR-680 may be turning because of support problems, especially for an established user base of return customers who regularly recommend your gear to others, just makes good business sense.