My Bersa Thunder 380 is rock-solid reliable, and a great gun to shoot. It is indeed a blowback design (barrel integral with frame; does not travel with the slide.) The Ruger LCP and LC9 are both recoil-operated guns, with "locked-breech" operation, meaning that the slide and barrel are locked together for at least part of the slide's rearward travel. That design reduces recoil over a blowback gun that is otherwise of equal size, weight, balance, and caliber. The two Rugers mentioned, however, are in 9x19mm caliber, so they'll still have some more bark and bite than the .380.
The Bersa Thunder series (9mm and .380ACP) are steel-framed guns. The Bersa BP9CC is a newer, polymer-framed model that looks pretty good; got to handle one recently at a gun show, but have never fired it. Unlike the Thunder series, which have external DA/SA hammers, the BP9CC is a striker-fired pistol.
The two Rugers mentioned are polymer-framed. Neither is particularly pleasant to shoot, but that's a part of "ultra-concealable" guns in service calibers.