We address accurate computation of on-orbit upset rates in advanced technologies, with a focus on FD-SOI at the 28 nm node. Heavy-ion measurements performed on FD-SOI SRAM bit-cells give experimental evidence of the technology's intrinsic robustness in space environments; this extreme reduction of sensitive volume dimensions deeply affects the assumptions pertaining to the radiation response models used to predict upset rates. The generic ``Integral Rectangular Parallele Piped''(IRPP) model, although requiring careful setting of its parameters, provides us with first-order estimates of the error rate. We then present a custom FD-SOI response model within our Monte-Carlo simulation chain, enabling comparison with IRPP and further analyses.