The product is very good. The 
 package did not come with instructions... if you dont have the experience of mounting a rangehood then you will tend to hire someone ... 
for an 860 CFM am amazed this hood is that quiet. My old rangehood which was only 290 CFM was more noisy than this one.... i would have given this item a 5 if it had the instruction with it. 
For the product and performance its a 5 stars