The first time I tried out a Sandberg was at the Bass Centre in Melbourne. They had several Sandberg models to demo including a number of 5-strings. Although it was a long time ago, I recall being impressed by the B-string, but it may have been the overall feel of the neck and spacing that I liked. I'll admit, I haven't been wowed over by the online videos of the Sandberg B-strings but with so many variable at play, it's tough to evaluate.My 34" Sandberg VM5 was what finally moved me to 35" basses, and I've not looked back since. Such a stunning bass with such a sub-par B string was a massive disappointment.
I'm currently looking for a 35" TM5, but I will admit that I'm nervous about that B string even with the extra inch of scale.
I'm hoping a 35" TM5 can replace my Lakland 55-02, because I'm having some personal struggles with the neck on that one, plus I really want a usable passive mode and tone control. However, the B string is a huge factor for me, and the B on the Lakland is absolutely stellar, so I'm only cautiously optimistic.
I had the same struggle with the Lakland 5-string necks. Incredible B-string but that 35" scale, 19mm spacing, and wider profile was not for me. And it's something that I didn't pickup on right away, only after playing it for a while. Anyway, I hope you're able to find what works for you.