Well, the .380 is still hard to find around here since the ammos shortage thing. I don't shoot it much anyway. I use whatever I can get at this time. My BT .380 is good about shooting any kinda crap I put in it.
Don't have a Bersa 9, but I have other 9s. Same for those guns. Winchester White Box stuff at Wally World works for me or the same quality ammo in Remmy or Fed brands. I will even use the Russian Tula Ammo if there is nothing else.
As far as accuracy. The accuracy varied from one gun to another even in the same brand and type of gun. Ya just have to try it and see what it does.
I have tried different brands and both Bersa's ate it all. Just wondering what bad experiences anyone may have had with a brand. Some Gun manufacturers don't recommend reloads and will not warranty their product if they discover you used them.
My thunder 380 has shot everything I have given it, very well I might add. The 380 ammo is hard to find around here also, however the range I go too usually has reloads from precision cartridge, I buy these whenever I go shooting there and my 380 shoots them just fine.
For just taking it to the range, I get whatever is cheap and easily obtainable. For example in my mosin I simply get the big surplus tins, I have a 9mm which I just get cheap FMJ's for, but have a magazine of JHP for defense purposes.
Get what is within your price range, but I wouldn't think too much about it.
If you don't mind reloads, I found some at http://www.freedommunitions.com/ last Thursday 12/20 and they had 177 cases of 500 rds at $154. Don't know how many are left today, but you might check. (I bought one case.)
Like everyone else said, the BT 380 just plain eats ammo. I've pushed Tulasteel and brass, Blazer, white box, Agulia, Buffalo Bore, Hornady, Barnes, Federal you name it and it chews it up. Some is less accurate or dirtier but it all runs.