Good evening Lythos, As Mentiras said this stats increases unmounted ground speed and it going from 125 to 150 is about a 20% speed increase.. its very worth having this as your pet will snap right to a target in active combat and is able to stay on mobs/players ezier... when the pub first landed there was no cap to this.. and ya could get Naj , wolves and other pets that had over 200dex that even speed hackers could not out run.. lol..for pvp reasons this cap is now at 190 which is paragon speed.. ya can get pets past this..but they still only get the effect up to 190.. if your older pets do not have this they are not ruined.. but will be alittle slower then pets that are 150.. when it comes to dex and stam you always want them maxed.. ..hope this helps mate.. =^-^=