I bought a bar scriber and have only used it once on a place that had old stone walls where it came in handy. Can't beat just using a cut off of the product your fitting imo.
I use a scribing bar a lot. Always on Lino work. I just find its much easier. I use unders and overs a lot too.
thats great lads cheers, the one i have is overs, never ever used to be fair need to see one in action really.