*sighs*
Why do people never read the OP properly before they post?
It is not my intention to buy this item in order to test its ability to withstand 2.5kV DC, I merely intend to test it so before I use it. Should I so desire, I could test its ability to withstand 10kV AC, but that's not my purpose here.
The fact the probe has no ribs/flanges to increase creep resistance should be indication enough that it's NOT a proper HV (vague definition) piece of equipment.
For reference purposes, 50V-10kV is intermediate voltage. High voltage starts at 10kV and above.
@tggzzz if I could provide a 1kV sinewave at 100MHz, I'd be a broadcaster, not an EE hobbyist. That is not a real world situation for this kit; if I was working on such gear I'd have expensive TE that my employer paid for.
@ tau, everything about this worries me, if I was dealing with signals at or near the advertised limits!
In reality, I will be using it at UK mains and rectified mains voltages, so nothing above 400VDC/250VAC or so.