Mine has Rangefinder but I'd say Rodeo is just as good, if not better. Rangefinder adds only 6% actual Range. Other than that it directly adds 16% to the fall off distance, which is its main effect, so if you aren't hitting the fall off, which you won't most of the time, it won't be too useful. It's better to pair with Smart Drift, which has a much bigger Range penalty. I'm not sure exactly how effective Rodeo is but from the guns I've used, it's much better than Counterbalance and is a good perk for sure. I think it directly alters the Recoil stat to lower the direction of the kick to make it more vertical and easier to control. Regardless, it's not worth a reroll. The odds are that you'll not get anything comparable without spending insane amounts of motes. The odds of getting AB/Rangefinder/PB/CC is insanely tiny at 1 in 378 rolls, requiring 756 motes of light on average to acquire. This is the reason why I didn't recommend a perk for the 1st slot. They are all pretty useful and choosing one makes your odds abysmal as there are 7 perks in that slot.