Quicker than an algebraic calculator, maybe, but very few people could get. faster with a slide rule than an ergonomic RPN calculator. like the HP 41 series. And I say that as an enthusiastic and experienced slide rule user, before I switched to a calculator.

One problem with a slide rule is that it only performs operations on normalized mantissas. You have to keep a parallel exponent calculation in your head, and that slows you down. Also, maintaining best precision slows you down.

When using a slide rule, keeping track of the number of digits to the left of the decimal point (DLDP) in the result is fairly simple if you know the basic rule:

For multiplication, the DLDP in the result is:

- the sum of the DLDPs of the multiplicands MINUS 1 if the multiplication is done with the slide sticking out to the right of the ruler's body (for example 2.0 x 3.0 = 6.0).

- the sum of the DLDPs of the multiplicands if the multiplication is done with the slide sticking out to the left of the ruler's body (for example 5.0 x 4.0 = 20.0).

There's a similar rule for division, but that's left as an exercise for the student.

I used an HP-41CV for many years. I needed the financial calcs module which I used in place of the dedicated HP financial calculator in grad school. Eventually gav out on me but was a good calculator for a long time.

I did keep a slide rule as a backup for exams in college when calculators were still LED but never really used one after a couple of years in high school.