Cs2Cu3SnF12 and Rb2Cu3SnF12 have a distorted kagome structure and the latter exhibits a pinwheel valence bond solid (VBS) state that has been demonstrated by inelastic neutron scattering. Here we will measure the critical behaviour of the Cs compound, test whether the VBS state persists to dilution fridge temperatures in the Rb compound, and investigate the structural transition around 200K in the Rb compound. Our samples have been provided by the Tanaka group whose earlier work demonstrated the pinwheel VBS state and have been characterized by a wide range of techniques. We have carried out preliminary measurements at PSI of these samples showing that the FmuF signals are present and change around the structural transitions, as well as showing changing fluctuations below 5K in the Rb compound. Here we will complete this work using the greater suitability of ISIS for these measurements.