Yep. Even if your going to run slower than 10.00 it wise to by a certified chassis if you can. If your goning to run 12-13 sec it's not a big deal but if you're going to be in the 10's it is a safety factor. My dad's car ('80 Monza) used to run 9.50's. It now runs 10.70's, different engine long story. We keep the cert up on it just in case. If you buy a car that is not certified, the cage could be thin walled as exhaust pipe and you wouldn't know by looking. DO NOT fall for "It passed tech at our track" That could be a lie and different tracks tech to different standards. They all have the same rules but enforce them differently.
Our track will pick a car apart sometimes. We have been to tracks that never even looked at our cars.