In our experiments, OPE-45 and OPE-s90 show similar transfer efficiency of 𝐼 1z 𝐼 2z spin order into magnetization, and both sequences have the same theoretical efficiency. OPE-45 relies on pulsed field gradients and rf pulse phase selection to suppress background signals, whereas OPE-s90 additionally suppresses background signals due to the frequency selectivity of its excitation pulses. On the other hand, the implementation of the frequency-selective pulse introduces some additional experimental challenges (e.g. requiring frequency drift of less than tens of hertz between experiments). It should be noted that alternative pulse sequences such as those in the Only ParaHydrogen Spectroscopy (OPSY) family can be utilized to generate in-phase magnetization from antiphase spin order, but these methods are not explored in this work.