I use both. My saddle bag carries two tubes and a patch kit. My bike purse (which goes inside a jersey pocket) carries 3 CO2 cannisters, an inflator, tire levers, a $1 bill, a multitool, a chain breaker, a spare quick link, and maybe something else I am forgetting. I also carry a mini-pump on another jersey pocket. For the winter I might add a bike satchel to bring warm rice cakes, rain gear, bluetooth speaker, and some deer food with me.