My physical therapist had me try a foam roll at her office and suggested that I get one for home since it had been a excellent way to stretch my upper back and thoracic outlet area where I was having difficulty. Despite being "hard" (these are not comfy, squishy foam but firm) it is incredibly relaxing and offers a great stretch by simply lying on it lengthwise and opening your arms in various positions including overhead. I understand there are also exercises and other uses which might make it even more versatile, but I am happy simply lying on it for 15 minutes per day and getting a relaxing stretch to maintain my improvement with P.T.
Concerning the size: I am rather short (5 feet)and the 36 inch length goes the length of my spine with a bit to spare, but a very tall person might find it difficult to "fit" on it lengthwise.
This model is a more expensive than the one that my therapist uses, but has a smoothed surface in black which I prefered to have around the house, and which I thought might hold up better. The only reason that it gets 4 stars rather than 5 is that this model is really identical in feel to my therapist's $10- model now that I have tried them both. The therapist's is white and a bit fuzzy from use...but has obviously held up with much greater daily usage. The asthetic is nice but I might have saved myself some money by going with the simpler white version. Therefore, I can't say for sure that the color is worth the additional cost since the durability of either would be equal.
Overall,though, this is a great product. Simple but very useful.