Best Online Store Option For YOU?
I've used Magento Go and Shopify. I've also used other Content Management Systems when I managed an Ecom team (for 7 years) including home grown and Magento enterprise.
If you want to start an online store which platform should you use? Let's look at a feature by feature comparison:
Easy To Use - Winner Shopify
Plugin / Add On Development - Winner Magento Go
Email Integration - Tie (both work well with MailChip et al)
SEO - Magento Go if you KNOW SEO, Shopify if you don't
Promotion - Magento Go if you KNOW ecom, Shopify if you don't
Manage SKUs - Tie
up to about 50,000 after than NEITHER (you've outgrown OPP Other People's Platform if you have more than 50,000 unique stock keeping units SKUs).
Cart - backend Magento Go
(can do more with logic so ASSUMES you know how to create business rule promotions) frontend (what customer sees) Shopify.
Templates - Tie
Pretzel Logic - Magento Go
(winning this is not a good thing since it means the platform has its own language YOU must learn or things go bump in the night. Magento Go is willing to be confusing and a pain to add POWER, but 95% will never use that power so if you have a small, fun store steer clear).
Cross Sale / UpSale
Slight nod to Magento Go again assumes you know ECOM well and cross merchandising is not intuitive but is powerful.
Overall Winner - Shopify
For most readers of this post Shopify is the best choice.
Magento Go honorable mention
for a specialized niche group that need powerful business rule based promotion, have between 30k to 50k SKUs and don't mind learning a new language to get the backend power they need. If you don't know your crosssale (what you do on a product page to move customers to more profitable or popular choices) or upsale (what you do in the car to build Average Order Value (AOV) then use SHOPIFY.