Which is better, normal PS2 or PS2 Slim?

The PS2 slim is a quarter of the size of the old PS2 however it has an external power transformer instead (probably as it wouldn’t fit in) and a top loader DVD drive. More importantly it has built in support for online games (ethernet port and modem jack). It also has an integral IR port on the front (the old PS2 you had to plug in a dongle). Other than that the new unit is the same as the old one.

there’s even a newer model ps2 slim with the transformer built in, but it came out in a limited number of countries, not sure if it came out in the US