I recently loaned a SP10 R owner after their hearing the impression it made, one of my heavier Record Spindle Weights that is 1400grams(1.4Kg).
When discussing the merits of the added weight with the supplier of the TT, they were informed that the TT has a max capacity for added weight as advised by the manufacturer of 1000grams (1Kg).
The following is from a review of the SP10 R and touches on the same subject about added weight to the Platter.
The main chassis is also cast aluminium. There are three speed selector buttons and a large square Start/Stop button. The unit runs at the default speeds unless adjusted, whereupon a small blue indicator LED turns orange. Turning power off then on returns to default speed, not last adjusted speed. However, dimmer and torque settings are retained at power off/on. A record clamp weight of up to 1kg is suitable, but not supplied. A rubber mat is supplied, but our pictures show the bare platter to reveal its construction.