Best cheap seats at the Sam Wanamaker theatre?

And just to set your expectations, remember that there are some of us who think there are no good seats at the Sam Wanamaker (even the expensive ones) - but it is certainly a theatrical experience worth doing at least once.

I sat in one close to the stage on the “sides” and I’ve never been as uncomfortable as I was for those few hours. My body faced one way and my head turned completely the other way. I was sore for DAYS.

Thank you everyone for your thoughts, that's really useful, sounds like this may be my only visit there!

It's worth going once at least - but of course their claims to be "authentic" are entirely spurious, particularly in the audience seating. 

I saw someone there once with a cushion with an attached back rest - an excellent idea if you are stranded on one of those bench seats not in the back row.

Quite. I thought I'd struck lucky some years ago when they halved the price of 'best' seats for the Gemma Arterton Duchess of Malfi.  I think we were in the middle of some extreme weather and people just weren't travelling (or even going out!) so stage side seats were going for about £35. Amazingly, the stage was set so the infamous 'waxworks' were displayed behind the backdrop so that from many of the side seats (£70+ at full price, remember) the punters literally couldn't see what so horrified the Duchess.  Since then I've always just got the cheapest possible ticket - usually standing - and last time (for Hattie Morahan in Ghosts) we got upgraded to front row of the gallery and, probably, the best sightlines I've ever had in the venue, on £5 tickets.  If I had to choose, the Pit looks best - but I've never sat there so don't take my word for it (and I don't think there are any cheap seats there anyway).

Fwiw, the explanation I was given was that the the SW replicates the conditions of an age when theatre audiences were more concerned about the social status of people they'd be sitting near to; and actually getting a clear view of the play was a rather minor consideration.  I've had some good evenings there but, honestly, as a theatre it makes a good museum.

Booked two - doubtless uncomfortable seats - to see Three Sisters. But looking forward to the experience!

All seats are uncomfortable but my advice is to go for one at the back so that you can lean against the wall. Oh, and end of row so you can stretch out your legs. Standing tix are their own kind of torture!