Best sounding Beethoven symphony LPs

The Kleiber recordings of the Beethoven 5th and 7th on DGG (2530516 and 2530706) do appear fairly regularly on eBay and with dealers. There are lots of them out there and, as many have noted, they are well worth the search. They should not be very expensive when found.

The Kleiber 5/7 is absolutely fantastic - good luck finding it.

Sonically the Vanska series with the Minnesota SO are impressive - some better than others - just issued the last two - they are not in a box set but come 2 sym. per package - in SACD. For the best performances in a box set go with Karajan's first cycle with the BPO - issued in 1961-62 - inexpensive for the box.

As a subsequent set, one has given me the most enriching experiences with the Beethoven symphonies yet: Scherchens mono set. I haven't heard everything, (who could?) but I've not heard more athletic, giddy, dramatic yet verdant Beethoven than this. As for the so-called "second rate" orchestras he used, I find most of their playing astonishing in regards to unanimity when reacting to Scherchen's often ultra-quick tempi. The mono sound is decidedly mono, but it's balanced from top to bottom and the early tube-cut pressings are pretty silky.

Thanks to everyone who took the time to respond -- much appreciated. There's a lot of good information here and I'm sure I'll have fun finding and listening to your recommendations.

Since my previous (useless) post, I have found that I actually have two boxed sets of Beethoven on LP:

Szell/Cleveland (1970) - avoid this one, for sure; sonics stink (very inconsistent, especially from side A to side B in the same symphony!), though I agree with some of the interpretatoins (the funeral march in 3 is just great!)

Toscannini/NBC - I have actually 5 sets of this. (don't ask) The recordings are great and the performances are great. The sonics (all mono) suffer from their technology, but are at the top of the pack for the time. If you can find this cheap and in good condition, get it and listen. I would not go terribly out of my way to find it, though, nor would I pay top dollar, but it is absolutely essential to have and hear.