Mick Bell (=Bloke) has been designing blanks and building rods in the UK for 20 years or more. He has produced 4 or 5 different blanks in that time. I think the XL50 was his first. Mick and his products have an excellent reputation in the uk. Take a look at the UK forum. Mick is very helpful and I don't ever recall any negative comment..
I have a couple of Bloke rods one ready built (SLP) and the other (xgnp) built by me, but not an XL50.