Execution speed - live account

Greetings, everyone

I’ll be moving from a sim to a live acct soon and I’d like to know how much execution speed differs between the two, during peak hours. Assuming that, say, a short order is placed as the price continues to rise, as momentum decreases and a cover order is placed as the price is rising - how much time might this take? Is the time typically measured in fractions of a second or a few seconds?
Thanks

I have been using Tradovate for years, it has to be one of the fastest and most reliable trade execution platforms available…lean and mean.

How fast, exactly? Assuming peak NY session hours

Thanks!