I'm in the market for a Stand Up Paddle (SUP) board mostly for surfing small waves and also flat water. Some SUP manufacturers refer to these boards as hybrids or universal. I'm compiling a comparison chart of boards that I think might be good for me. (Link to download the file at the bottom.)
The criteria for selecting a board includes your weight, skill level, and the type of water you want to paddle on (flat water, surf or both). You will also want to consider the weight of the board. You should be able to lift it over your head so you can put it on the roof of your car. You need to carry the board to the water.
Volume describes the amount of buoyancy or float. I prefer a board that's flatter so the volume is dispersed across the width of the board making it more stable. I'm a windsurfer, but not a very good surfer. My most buoyant windsurf board is 150L. This is the minimum volume for a stand up paddle board. I think more may be better. Rent a board before you buy it if you can. Many shops have demo events.
Here is a link to the SUP stand up paddle board comparison chart I'm working on so far.
> Download Stand-Up-Paddle-Board-Comparison-Chart-Matrix