Which of these CMS platforms are best for eCommerce industries? Magento, Interspire or wordpress?

Magneto is best e-commerce platform so far but if you are looking for some small scale app then you should try the Prestashop. It is easy to customize and rich in modules.

Magneto is best Platforms for Ecommerce

simple eCommerce  (wordpress with plugins).

mid   eCommerce (magento).

advance eCommerce (interspire).

Magento is a best and secure for eCommerce

For small scale E-Commerce website and low budget, i will prefer WordPress because its easy to understand, easy to learn and low cost for maintenance. But if you have large scale Application and having Good budget then i will prefer to go at Magento because you have bear the cost of Development and Maintenance which is really HIGH as compared to WordPress.  

According to me magento  CMS  is best for E-Commerce website .

Magento is best but for small ecom websites wordpress is also fine

If you are doing a small ecomerce site, then you can choose wordpress. Other wise its better magento.

Megento is good and is siutable for large projects, if it is normal e-commerce project consider "Open Cart" or use plugin for Wordpress.

It depends on how big your ecommerce project is. If it is big then go for Magento, you will have to see for the paid plans and if you are comfortble with the charges go for it. Otherwise you can try Wordpress, where you can purchase an ecommerce theme and start building your website. It is easy and with some great plugins you can easily start your ecommerce website. For integrating a payment gateway you will have to opt for a piad version of woocommerce, etc.

Magento is best eCommerce solution, I am working on it from many years and from day start it's growing faster.