Mono vs. Stereo LP's

Thanks everyone for your comments on judging LP's based on their condition (see prior thread). What about mono vs. stereo? My dad has a great collection of mono classical LP's from the 1950's. The way I figure it, it's only worthwhile if the performing artist is only captured only at that time, at that performance, and it not available on a stereo LP. What is your experiential wisdom about taking in mono LP's? What are the points to consider?

I'll probably get smoked on this one but here goes. First, I'm not a classical music lover but appreciate good recordings of any kind. The '50's era mono classicals are some of the best. Having been to a few classical concerts I find that the mono's come closest in recreating the live event. In fact, where I sat at these few concerts, stereo simply wasn't part of the live event. IMHO, of course.
Peter, don't be too quick to dismiss mono LPs. Many early stereo recordings panned instruments hard left and hard right in a most unnatural manner. The soundstage artifacts distract immensely from the quality of the performance. Even today, recordings with strange perspectives and distracting effects are frequently found. If it's about the music, not hi-fi, mono can be quite rewarding. Oh, and don't forget all the money you can save by not having to purchase that extra Martin Logan Monolith; fits into your living room better too.