The following commentary comes from an independent investor or market observer as part of TheStreet's guest contributor program, which is separate from the company's news coverage.NEW YORK ( Magic Diligence) -- Who hasn't heard of Vonage ( VG)? One of the pioneers of the voice-over-IP telephony business, the company came to prominence with aggressive marketing and rapid revenue growth in the middle of the last decade. It also earned infamy in the investment community, badly botching its 2006 IPO by soliciting its customer base to participate, fighting off patent infringement lawsuits from several wireless carriers, delivering massive net losses, and also working up an ugly balance sheet with crippling debt terms and dilutive stock warrants. So you can imagine my surprise when the stock showed up recently in the Magic Formula Investing lists! Like most, my impression of Vonage was formed from the highly negative coverage of the stock several years ago. But after some research, I believe the firm no longer deserves such a bad rap. Let's take a look. Follow TheStreet on Twitter and become a fan on Facebook. For those who don't know, VoIP is a service that allows you to make phone calls over an Internet connection instead of a wireless voice network or traditional landlines. VoIP calls can be made over any Internet connection, be it cable modem, DSL or 3G/4G wireless data networks, using an array of devices including telephones (with an adapter), cell phones, PCs, and so forth. VoIP services such as Vonage's generally include wireless-like features such as caller ID, call waiting, visual voicemail, etc. Vonage has about 2.5 million subscriber lines, about 95% of which are in the U.S. The main allure of VoIP is the lack of long distance charges. VoIP-to-VoIP connections are usually unlimited for a single price, while VoIP-to-landline or wireless calls may involve an extra fee as it requires third party carriers to connect them. Given this fact, Vonage changed their marketing strategy in 2009. Previously focused on broad national marketing, the company introduced the Vonage World plan, with unlimited calling domestically and to over 60 countries including India, Mexico, and China. This makes the service quite attractive for recent immigrants or students with friends and family overseas.