I did not run any benchmarks and OTP is not directly comparable to GraphHopper as feature set is quite different. So this is just my impression an take it with a grain of salt.

My impression is that GraphHopper is fast and does not take much memory whereas OTP feels quite "heavy" on comparable datasets (city-area level OSM data). So my hope is that if GraphHopper would support timetable routing with the same quality, it will probably beat OTP.

My ultimate goal is to have open-source based multimodal routing on the coutry level (Germany) which would include public transport as well. Frankly, importing country-level datasets in OTP seems unrealistic. GraphHopper on the contrary seems very promising.