Thanks Kent and John for your replies,
I do have a W1GHZ ratiometer so some sort of antenna range should be possible. However, my aim is to get on the radio for a change and I won't be building a box of 8 anything! I've already had a suggestion to make a DL6WU yagi as well and compare; perhaps after the first 100 QSOs.
I'll build a simple 2m-long loop yagi first, I have the material to hand and a metal former to roll the elements. In principle I could CNC drill the holes but it'd take longer to set up than the mandraulic method.