Are you in a NTSC or PAL region?
For PAL, the EH57 works great though it has the same brightness issues as with the ES10, otherwise it's quite similar, a tad less strong jitter correction on "extremely" bad tapes, though has a higher bit depth video decoder and HDMI output. If it's a US/Canadian variant it may not work well at all as Panasonic started using different chipsets for models from that year on and I know at least some of them have a very basic video decoder chip.
The PAL Panasonic DMR-HS-2
seems to have similar jitter correction as the ES10 according to a user here, though I have no idea about transparency compared to the ES10 and later other than that the menu-activated DNR function is
reportedly not active on pass-through. I haven't seen any mentions on whether or not it has the same white clipping issue as later models though I suspect it might since otherwise e.g the gleitz forums would probably be more adamant in suggesting the old models specifically.
The 520 and 720 do not work well either as far as I know. I haven't seen any HXDx90 models specifically, though it seems to be based on the same chipset as the RDR-HX750 that I know works, just with a digital tuner, so of these alternatives, if you want something different to the Panasonic, I think you would want to go for either the DVR-530 or that one.
As far as I know, the PAL Panasonic DVDRs don't have the posterization issues that has been reported with the NTSC variants, the only transparency issue I know with them is that they tend to clip very bright spots (which can be
worked around to an extent with a volume control or potentiometer or similar).
The plus points of the pioneer/sony models don't have the same problem as they let you adjust brigthness, contrast etc. They also have a soft border on the left/right compared to a sharp one from the panasonic models on the analog outputs. (The HDMI output gives you the whole 720 pixels on most dvd-recorders.) Mostly noticeable on PAL, NTSC usually has smaller areas blanked I think. The other plus point is that they do not turn off the analog outputs if the dvdr thinks there is no input connected like the panasonics. Usually that's not an issue but you can encounter it on tapes where something has been recorded without the video input connected. There are also going to be some minor differences in Y/C separation if using composite input but I can't really tell which one is better at it.
Also, at least for PAL Panasonic and Sony/Pioneer models give flashing brightness or half the image being darkened if the input has copy protection (Though I seem to remember that for the RDR-HX750 at least, the using HDMI may avoid it, but I'm not able to test that at the moment. HDMI does not evade it on the EH57.)