As far as numbers go the TVC-33 and the TVC-34 are pretty close in popularity throughout the SOAR market. They both extend to about the same height +/- .5 inches (TVC-34 being .5 inch taller). The main difference comes with the pack-ability. The 34 will collapse 5 inches shorter than the 33 version.
If you want it easier to pack get the TVC-34, if you want the fastest setup possible go with the TVC-33.