Depends? Haha. Who are you buying from?
If you are buying from a reputable source then of course you need to ask them about the quality of their material. Today's bonded leather can be
very high quality and isn't the same as the pleather from the past. There are claims that some is actually more durable than mid grade leather.
That said, I paid a little extra for leather on my chairs as my wife was skeptical about bonded leather and we were buying online (sight unseen).
As with everything the source is the key. Buy from a dealer you can trust and has a good reputation.