A client of mine uses Plesk,hate every time I have to login into it,so you can imagine which of the two I preffer
Plesk is good, but personally i feel cPanel is the best web hosting control panel ever designed, i found every feature excellent and not one lacking in anyway.
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cPanel was the first control panel. All others came after. That's why cPanel is the best. They've had more time to improve it. cPanel started when the hosting business was basically just starting. Since then, it's been built upon to stay up to standard with the industry. They also provide good support.
The hosting company that I use offers both cPanel and Plesk. They say that 70% of people choose cPanel.
"Democracy is two wolves and a lamb voting on what to have for lunch. Liberty is a well-armed lamb contesting the vote." -- Benjamin Franklin