Hi Jorge22f,
It's unfortunate that when you're new here you're really stuck to posting in this section of the forums and let's face it, the majority of visitors won't head straight for the 'newbies' section.
I'm using Block Errupters myself and it's clear they're no longer cutting it. I'm lucky if I mine 0.25 BTC/month with 20 of them. It was an interesting first venture in ASIC though
Perhaps you could email support at your preferred supplier a few times to see how quickly they respond to you and place a smaller test order to ensure that they fulfil it in a timely fashion. If you're paying in cryptocurrency then you could ask that they use an escrow service for a small fee.
There's too many scammers out there these days - be safe!