Is WordPress Safe For E-Commerce?

I’ve never built an e-commerce site using WordPress but today I have one of my clients require an online store for his business so I’ve make my research and find some negative points regarding using WordPress as E-Commerce Solution especially Safety issues! the question is WordPress Secure for Online transactions?

During my research I’ve found that core WordPress files are to some extent safe and the threat my come from four issues:

1) Used Plugins

2) Used Theme

3) Hosting

4) Database

So it is essential to use premium plugins such as “WPMU Plugins” For ex: MarketPress Plugin and I can find good themes here also. so what remains hosting and database! what hosting you recommend and how to make WordPress data more secure. also I’m wondering how can customers data can be hacked in case I’m using gateways like authorize.net since all transactions occur there not on actually WordPress Site.

I know there are special scripts for E-Commerce like: Magneto, Shopify and so on but I’m not familiar with them for that I prefer WordPress, also the look and usability in WordPress is better.

Finally any recommendation for safe plugins, tweaks and tips.

Thank you,