Instruct: Classify Amazon reviews into positive or negative sentiment
Query: worked well from the moment they were installed

I was looking for the best and least expensive. First I've got Komputerbay 2x1GB for $40, but only one worked. I returned it and as always, Amazon stayed behind their products sending a quick refund. Than I decided to spend $5 more and got this PNY OPTIMA. I opened my computer for the 1st time in my life so I've seen how this modules look like (and yes, cleaned my computer). The bottom line is that both of the modules worked from the very beginning, without any problem. There was a big chance that if I would have given another try to Komputerbay, that set worked fine, as another costumer said in his review. But this one fitted my budget, so I thought it was a pretty good deal. And they got to my door in one or two days. That was very nice also.