+1
Aside from holding more rounds, Bersa 13 rd magazines seem less likely to bind or have other problems than 10 round ones, though I will point out any sort of problem happens VERY seldom with either magazine. My guess is it has to do with the material the followers are made of... metal vs. plastic. BTW, the easiest (and quickest) way to tell a 10 round mag from a 13 round Bersa UC magazine is to look at the magazine follower. A Bersa UC-9 13 rd magazine's follower is chromed/polished metal while the 10 rd mag's follower is black plastic. Otherwise, they look exactly the same. A polished metal-on-metal follower is less likely to "grab" than a plastic-on-metal one and a metal follower is also less likely to scrarch or deform than plastic. Actually, it may be one reason there are more feeding problems with the UC-45... they have a plastic follower instead of metal followers like other Bersa's, including the 380.
FWIW full size T-9 magazines are longer by 3/4" than UC-9 magazines, but they will work in both models, while compact mags will NOT work in the larger guns. Also, pre/post Clinton AWB era mags for the T-9 hold 17 rds while the Clinton era magazines ~ and those sent to states like Kalifornia with magazine limits ~ hold only 10 rds.
Thunder 380 & 380 Concealed Carry
Thunder 9
Ultra Compact 9 (2+)
Ultra Compact 45
... among others