This is a controversial subject that has been beat to an absolute pulp on this site. What it boils down to is that sucking it out will get the job done and is convenient, but it robs you of the opportunity to inspect under the car on a regular basis, plus the contraptions that are used to do it are not cheap.

Most likely you already have what you need to drain oil from the bottom, a wrench and a drain pan.

If someone gave me one of the contraptions I would not use it. Many of them do not allow you to draw the oil while hot. I drain my oil while it is as hot as possible so that the crud is churned up in the oil and will drain out. I can let it drain overnight so that ALL the crud comes out.

Depending on the car, there are certain things that I always check for when underneath for an oil change. Mainly you look around for leaks. If there are any leaks you will see this from the bottom long before you will see most leaks from the top. It also gives you a chance to shake things around to see what might be loose. Start with the wheels and then steering parts. Inspect the rubber boots on tie rod ends and ball joints to see that they are not torn.

It's your car and your choice. The most important thing is that the oil be changed and changed often, regardless of your chosen method.

Good luck,