Not sure about how it'll work on a London but I have my Becker Legends strung at 35/33 with Black Code 18 and find it very comfortable as well as providing a lot more spin than a multi at mid-range tensions. For me low tension poly also seems to offer a slightly longer dwell time and I prefer that feel. But the spin I get from poly is the big thing for me and the low tension addresses any harshness issues. I've been playing with low tension poly for more than a year now since I came across the thread in the string forum started by Chris of TW on his low tension poly experiments with the PB10 Mid. It took me a while to get used to it initially on the PB10 Mid as that frame seems to be more sensitive to angle of the racket face at contact and the low tension stringbed made this even more acute. I found that I needed to be very accurate with my strokes on that frame. With the Legend, the transition from multi to low tension poly was seamless. In any case I find the Legend to be a much easier frame to play with than the PB10 Mid, all else being equal. So I think low tension poly is worth a try on the London (or any other frame for that matter - it's my preferred string option now) but based on some of the posts I've read, some people never adapt and switch back to higher tensions. From my perspective, I think that mid-40's is still too high a tension! Especially with modern stringing machines which seem to apply tension more effectively. Of course we all have our different preferences but what I'd say is don't be afraid to try what seems to be ridiculously low tensions. One of my Legends is strung at 33/30 and it's a bit too mushy for my taste but still quite usable.