can anyone please suggest me a reliable USA/SG based hosting provider?

I will be doing annual billing so need a reliable provider. (have bad experience in past)
i need about 30GB disk, 500 GB bw and fair share of memory and cpu.
I currently have 4 wordpress sites to host, avrage daily traffic is around 10k-15k.

budget $20-30/month
Do you think that QHoster.com is reliable one? Have you ever heard anything about them?