I'm using the 238.4s and I love how they play. They are at the edge of stiffness that I can use. I have tried other strings but nothing plays as well as poly for me.
I have a bunch of IG Prestige MPs but I haven't modified them to my specs - they would probably be a bit better for my arm compared to the YTs. I've added a lot of lead at 3/9 on the YTs and that really helps in stability and arm comfort.
What's interesting on the IG Prestige MPs is that I don't need the lead at 3/9. So I guess you can either go back to the MGs or go forward to the IGs.
4 x IG Prestige MP, 70 cm, 376 grams, 386 SW, ALU Power @54, Prince Syn Gut 16 @58