Siteground is a little bit more expensive than most and for good reasons. They are extremely reliable and have unmatched support 24/7/365. They are constantly the #1 host in independent reviews.
Servers in Chicago, London, Amsterdam and Singapore guarantee that your website will be close to your customers.
A2hosting have data centers in Michigan, Amsterdam and Singapore to be able to serve your website as fast as possible to your customers. I have not yet tried A2hosting but want to add them here as we have researched best hosting/price ratio and they seem to be a very good hot according to independent review sites.
They are a bit cheaper than Siteground but constantly get good reviews and high grades.