As an AI language model, I don't have personal opinions or preferences. However, I can provide you with information about popular eCommerce stores based on user reviews and market statistics.

One of the most well-known and popular eCommerce stores globally is Amazon. It offers a vast range of products across various categories, from electronics and clothing to books and groceries. Amazon provides a user-friendly interface, reliable customer service, and fast delivery options. The company has built a reputation for its extensive product selection, competitive prices, and convenient features like one-click ordering and personalized recommendations.

Another popular eCommerce store is eBay, which operates as an online auction and shopping website. eBay allows individuals and businesses to sell new and used products through its platform. It offers a wide variety of items, including collectibles, electronics, fashion, and more. eBay's auction feature allows users to bid on products and potentially find great deals. Moreover, eBay has a robust buyer protection program, which enhances the trust and safety of transactions.

In the fashion industry, Zara is a renowned eCommerce store known for its trendy and affordable clothing. Zara's online store offers a seamless shopping experience, allowing customers to browse and purchase the latest fashion items. The company focuses on fast-fashion, constantly updating its inventory with new designs. Zara's success lies in its ability to quickly adapt to changing fashion trends and deliver products at competitive prices.

For tech enthusiasts, Newegg is a popular choice. It specializes in electronics and computer hardware, offering a vast selection of products at competitive prices. Newegg provides detailed product descriptions, customer reviews, and comprehensive filtering options, making it easier for users to find the exact tech item they need. The store also offers various deals, discounts, and promotional offers, attracting a large customer base.

These are just a few examples of popular eCommerce stores. There are many other successful platforms like Walmart, Best Buy, Alibaba, and Shopify, each catering to different markets and customer needs. It's important to consider factors such as product range, pricing, customer service, and user experience when determining your favorite eCommerce store.