Pendlay Row is not for everyone. It depends on how strong your hips are in maintaining that parallel position to the floor.

My advise is, like everything else, start light and practise on form first. Try not to swing back and forth. If you are, probably going too heavy. If done wrongly, can hurt your hip and lower back. So be careful.

Just a suggestion, don't do it as explosive movements requires practise and good form. If your posture doesn't allow it, replace it with something else or correct your form using just the bar.

I learned my lesson the hard way....

Exactly, Pendlay Row mainly engages your core strength every time you move into position. For Pendlay Row to be effective though, you will need to go heavy to target your overall back. Question is, can your core take it? How many reps before you start swinging back and fourth? Its a dangerous move if done wrongly.

If you are using Pendlay Row as an assistance exercise for the Deadlift, like Bafukie said, Rack pulls can be a good alternative.

Then again, all exercises can be dangerous if done incorrectly. Form, at least a good one above all else.