A selection of simple composite design (mechanics) equations were introduced in Chap. 2 to enable prediction of the mechanical properties of fibre-reinforced composites (FRCs). The rule of mixtures (RoM) and inverse rule of mixtures (IRoM) expressions were introduced for elastic moduli estimation, whilst longitudinal strength was considered via the Kelly-Tyson (KT) model. Chapters 3 and 4 then introduced wet layup, and vacuum bagging and prepreg moulding methods for composite manufacture. A carbon fibre-reinforced panels was fabricated using similar constituents (i.e. carbon fibres in an epoxy matrix) for each fabrication method. This chapter builds on these earlier chapters via a comparison of design (mechanical property) estimates and experimental data. Tensile tests are performed on multiple specimens cut from each of the panels. This chapter provides guidance on the accuracy of design estimates and offers support for the typical (rule of thumb) volume fractions suggested in Chaps. 3 and 4 for each manufacturing approach.