When it comes to A/V, I'm a purist. With my audio, I don't want anything messing with the audio, no DSPs, no tone controls, no equalizers, no MCACC, nothing. I want the original, the way it was intended. The same goes for the video. If something was mastered a certain way, it was done that way for a reason. Who am I to think I can do better than a recording engineer or the director's vision.
Also a good sign of high performance and quality is the electronic's ability not to change the signal from it's original form. It should behave as passive as possible. This is the reason why digital audio is preferable and why recording CD tracks digitally, over analog, is the preferred method. With a very high quality CD recorder that has excellent analog circuits, this isn't such a problem but with lesser recorders it is. My HK CDR20 has been tested to have some of the best analog circuits to maintain the original signals, over many others tested in it's class. I expect my DVD recorder to have the same high performance especially since I have no way to record a digital video signal or a digital audio signal. Keeping the signals in their original form is the best way IMO.
BTW, I'm not totally biased, I love Sony's Minidisc recorders. I think they offer some very good lossy encoding and playback is very good. Of course, it's lossy and is why I now have moved on to CD recording. However, Minidisc is the best for editing and ease of use. I really wish minidisc would have caught on but Sony killed that format from lack of advertising and promotions. They'll most likely do the same to SACD judging from their current actions.
All in all, DVD recorders are the highest performing video recorders next to S-VHS VCRs(and the new D-VHS recorders). Either being better based on that formats models. However DVD has the advantages of a Disc format with it's conveniences, low media expense, and much higher compatibility with DVD-/+R discs. I believe this Pioneer DVR-510 records a better picture than my JVC S-VHS VCR, but the Panasonic DMR-E80H did not.
My bias against Sony most likely wouldn't be so strong if they actually priced their products by quality offered and not name recognition. The Sony DVD recorder being a good MSRP $450 recorder since it lacks many functions of the other recorders and performance being questionable if it's worse than the lower price competition. The same goes with their TVs, they're just to expensive and offer to little in the line of performance compared with their higher performing competition. They do offer nice feature except that crappy DRC processing which adds way to many digital artifacts to even be usable. Once that DRC is turned to it's minimum setting, only then does the picture become acceptable. My buddy had just bought a brand new Sony KV-40XBR800 (that being the world's largest tube television and Sony's flagship tube XBR) and was ready to take it back over the poor picture. His 68 year old father even noticed the degrading artifacts and made negatives comments to him over it. He called me over to see if it could be fixed before sending it back. After we turned the DRC to min., was it better. This feature shouldn't even be offered, let alone, defaulted to such a poor setting. Well anyhow, that was our opinions on this Sony flagship set.
Have a good one.