I am transforming 3 different vectors in E coli competent bacteria: cDNA3.1, Pe16b and Pe28a+. I used the same protocol (heat shock) for transformation and plating ( agr + appropriate antibiotics).
I was successful with cDNA3.1 ( 4 vectors ) , pe-16B (1 vector with low quantity 10x less then cDNA3.1) and 0 clone for pet28a+ vector from addgene.