If you are planning to host 1-3 websites than you should go with just shared web hosting. When you decide to go with reseller web hosting. Depending on your choice of web hosting provider, the server your reseller account is placed on maybe filled with a lot more web hosting accounts than compared to a regular shared server.
Reseller web hosting accounts are meant for businesses that want to resell web hosting services. Most people that order reseller web hosting accounts intend to resell web hosting. Whether or not they can oversell varies from web host to web host but on a reseller web hosting account you can expect a lot more domains to be hosted than a regular shared hosting account server.
With more neighbors on your server you can expect less CPU and memory resources available for you to use. Different times during the day the server may grind to a halt or may experience slow performance. If you plan to host a lot of websites than a reseller account may suit you but if anything less than 3 websites than you should consider staying with a shared web hosting account.