You have already received a couple of recommendations on a well-regulated broker, and that’s the most important factor when choosing where to trade. Recently, there have been several discussions on this forum highlighting the dangers of trading with unregulated brokers:
Since you’re particularly interested in trying a demo account on the MT4 platform, you’ll be interested to know that FOREX.com is unique among US-regulated forex brokers in supporting desktop, mobile and web versions of MT4. That means you can access our MT4 platforms whether at home, the office or on the go.
We are also the the largest forex broker in the US based on client assets. That means retail traders have more money deposited with us than any other forex broker based on the latest data from the CFTC, which regulates forex trading in the US.
Thanks to our size, FOREX.com is able to offer you with customer support to answer any questions you have about your MT4 demo account with us 24 hours a day during the week via phone and live chat, unlike smaller brokers that limit their support hours to certain times of the day. Since you only have limited time during the day, it’s good to know you can reach your broker anytime day or night, since the forex market is open 24 hours a day.
Demo accounts are free, so they are a great opportunity to test the customer service of multiple brokers. FOREX.com demos default to 30 days, but that’s easily extended if you want more time to practice. In addition to our 24-hour live support mentioned above, we also have dedicated discussion thread on this forum, so please feel free to reach out to us anytime with questions: FOREX.com discussion