Depends which you want more …. delays or reverbs.
TimeFactor is a great delay pedal, but it is more or less just delays and different flavours of delays …you can get some chorus and a slapckack kinda reverb.
Space is a GREAT pedal … it IS a reverb pedal and it does great reverbs … but you can get other great effects out of it too…
IMHO Space covers more ground….. but they are not really directly comparable with each other.