Choosing a bowl is an individual thing and one should taking into consideration a few pointers. The weight of the bowl, the size is it a proper fit, comfortable and the grip: can you grip it without it slipping.
Indoor and Outdoors.
Remember there is a difference between indoor and outdoor playing greens and this should be taken into account. A bowl played indoors will take a wider arc than if played outdoors. Some bowls are best suited to either indoors or outdoors and some can play on both surfaces.
One method to get the right size, in conjunction with feel and comfort is to put both hands around the bowl with the middle finger touching and the thumbs touching at the bottom.Now try and bowl the bowl to see if it is comfortable. If it falls out or you fingers go white griping it go down a size and try that..If you feel you have good control then that will be the size for you.
At Adventure1 you can try out bowls on our indoor carpet.