Eugh, can't stand Grahame Knuttels "art" - too garish although it's popularity would make it a fair investment.
Had a funny incident with the man himself, we happened to be in the same company at a very small bar and he was introduced to me (by his wife) as Grahame Knuttel - the artist! Cringe or what? So I felt it necessary and if only to be polite to comment on his art. Unfortunately as I'm not a fan the conversation didn't last long, I was extremely gracious as was he. However, his wife tapped me on the shoulder and quietly said that Grahame didn't like discussing his work when out on a Saturday night so I advised her not to introduce him as Grahame Knuttel the artist in future. She wasn't pleased.
I had a great night.
Sorry off topic.
Yes art is a good investment, as long as you like it.