Spike does additional processing per sweep that could be slowing it down a bit. You should measure the sweep times using the API for an accurate number to see if it would be adequate for your application. The BB60C doesn’t have any sweep queuing mechanism, so you incur the over head of processing and USB latencies for each sweep. 6-7 ms is probably the ball park for the fastest possible times.
We don’t have an SM200A demo/loaner program. If you are outside the US, your distributor might have a loaner program.
Regards