The tgk238.4 is a YT Prestige MP. I find that they feel awful at very low weights but I like them at my comfortable spec range. The tgk238.4 is a platform - you can do whatever you want with it.
I have two tgk260.2s as well - leaded up to 13 ounces. I'm sure that they play nothing like the YT Radical MPs in stock form.
I think that the Radical line was softer than the Prestige line in the YTs.
VSB's description of the YT Prestige is brassy.
4 x IG Prestige MP, 70 cm, 376 grams, 386 SW, ALU Power @54, Prince Syn Gut 16 @58