If the pattern allows it Ruth I add a 1/4" (or cm if I'm working in metric) to the cut length of the card, butt up against the bar and round up to either 1/2 or whole then trim that 1/4" off when I'm finished.

The wrmk cut & score board isnt bad, so far mine's cut straight, square and accurately in inches. I'm not soo keen on cutting before scoring as I havent found the flip over lid you butt against to be perfectly accurate, so I tend to score and cut while the card is anchored. Not quite as impressed if I want to work in metric as the cm markings arent easy to spot when I havent got my specs on, they're written away from the top ridge so I'm fairly likely to cut the card squiffy or have to guess if I've got the card at the right size.

For me, in an ideal world I'd have the hougie for most of my boxes and non cardmaking. Scorpal metric for scoring a4/a5 in half/gatefolds, wrmk envie punch board for envies and MS for the rare occasions when I need to mess about with fractions of inches. I've been saying I'll get an MS board at the next craft show when I have money burning hole syndrome for a few years now but I always find something else I want more. The wrmk trim & score might make me change my mind as I use it more & more but I bought it primarily as a trimmer.