Obviously, there are two sides to this issue.

I am going to take one side of the "no demo" argument.

One of the few advantages to spot forex is the fact that one can open an account with some brokers with a little as $25.00.

Now let's assume you are like a lot of people and spend $5.00 a week day on a Latte from Starbucks. 5 x 5 = 25. So that’s $25.00 a week. There are roughly 4 weeks in a month. This gives us 4 x $25.00 = $100.00

So if you forgo a months worth of visits to the coffee shop, you can trade live with an amount of money that wont hurt if you lose it. If it would hurt, then you should not be buying coffee in the first place, because you loose that same $100.00.

For most people, losing $3.00 in a real account has a different effect on the psyche than losing $3.00 in a play money (demo) account, even when they attempt to trade the demo account "as real as possible". The sooner one can recognize and overcome the inner demons that surround loss/risk/self worth, the better. If you don't have any, then you are ahead of the game. But trading demo wont tell you if you do. A small real account will.