Well, I ran a rewired RB300 with a Cardas Heart on an LP12 Lingo for a number of years. The tensioning spring was removed during rewiring and the VTF was set with the counterweight. There was no problem whatsoever with setup or installation, or with day-to-day operation. My Linn dealer did not recommend using the Heart in the previous arm, an Akito, which I understand is a better arm than the Basik, indeed the best MC he would go for was an AT OC9. The Heart worked really well in the RB300.
I have pics of the setup if you like.
I have pics of the setup if you like.