The modern alchemy potions have a set casting level built in which controls the run speed you get from the potion's Spirit of Wolf (or Pack Spirit) buff.
run alchemy alchemy velocity target skill cost to make Base run speed : 30 Philter of the Wolf I : 40 (+35%) single 75 0.544 Philter of the Wolf II : 42 (+40%) single 100 1.832 Philter of the Wolf III: 43 (+45%) single 135 2.619 Philter of the Wolf IV : 45 (+52%) single 170 4.457 Philter of the Wolf V : 46 (+55%) single 210 6.819 Mist of the Wolf I : 43 (+45%) group 250 8.919 + Robust Shadow Essence Mist of the Wolf II : 46 (+55%) group 290 11.019 + Exceptional Shissar Blood
Philter of the Wolf V is the potion to make and use. The lesser potions are only if you lack cash or alchemy skill. The single-target Philter potions are made using all store-bought components, while the group Mist potions require farming drops. These potions are useful for characters under level 51 who don't yet have run speed AA.