Comparison-shopping is becoming the mainstream marketing channel for B2C ecommerce. More and more small online vendors are using shopbots to bring in customers. There are mainly two types of shopbots: those general shopbots that provide product comparison cross multiple heterogeneous product categories (like shopping.com) and the specialized shopbots that provide comparison within a single or a few highly-related product categories (like addall.com on books and music CD). The effectiveness of shopbot selection strategy by small online vendors is the focus on this paper. By analyzing data from shopbots and online vendors, the authors found there is significant positive correlation between the number of shopbots an online vendor participates and its traffic rank, which indicates the general effectiveness of using shopbots as a marketing channel. They also found that for online vendors competing on a niche product like college textbook, participating specialized shopbots brings in higher traffic. For competing in mainstream market, there is less significant correlation between participating general shopbots and higher traffic rank for vendors. They conclude that using general shopbots is a reactive strategy for small online vendors while using proper specialized shopbots could provide an edge for small online vendors.