Believe the product deserves a 4.5 or 4.7 rating. Overall quality and ease of use for 85% was excellent. I did run into the problems of warpage, cracked pieces, and poor finish on about 10%. I had a fairly large project and used about six pro packs, so I boxed up the equivalent on one smaller box and returned them to my local store with no problems at all. As to installation, I read several reviews about wood cracking, etc. Well, this is 1/4 inch hard wood. You can't hammer like your using a 2x4 and you can't use large nails. Be careful, and you should not have problems.
A couple installation suggestions for medium to large projects:
1) Use a brad/small nail gun if you is available.
2) Make sure all your studs are clearly marked, top to bottom, before beginning. This makes nailing and marking pieces to cut very easy.
3) If you have or can borrow a power mitre saw, use it for cutting.
4) I did floor to ceiling on four walls and followed do it yourself guidance form several sources - starting at the bottom. Because I did not want to put molding at the ceiling, I had to rip every panel around the top edge. Unfortunately, I don't have a table saw and had to do this with a hand held circular saw. My suggestion: if the ceiling line is reasonably straight, start there. If you have to rip panels, you won't have to be as exact as I had to be because the base board will cover rough cuts.