Glad I did a search on this topic before posting new. I see there are 2 versions: 8,000 & 12,000 and that most have the 8,000 ramps which is good info. My car is not lowered nor do I have plans to lower the car at this point

Here are my questions:
Do both sets of ramps (8,000 or 12,000) have the same angle and clear the same when driving up on them? I just want to make sure there are going to be no issues with rubbing or damage to the car.
Is the clearance good both ways? Driving up on them with the front or backing up on them with the rear of the car?
I see that Joe talks about needing 2X6s... Is that only if the car has been lowered?
Are there any better lifting options that are affordable?
Thanks in advance for your help!!!