Here's what Vic Firth says about the Nova:

Made of hickory with your choice of either wood or nylon tip, these are a great value for the beginning player or musician on a budget. Get Vic Firth quality at an extremely affordable price. Slightly heavier than 5A sticks, these wood-tip sticks are perfect for rock.

Size Guide:

As a guide, thinner sticks are better for playing lighter musical styles such as Jazz. Typically suitable sizes are 7A or 8D
For those playing pop styles through to the lighter genres of rock-pop or indie, 5A is a good compromise of weight.
Rock demands a bit more power, so a meatier stick is in order. A 5B is good option for rock to heavy rock.
For those playing the heaviest styles of metal and rock, where power is everything, the super-thick 2B sticks are a great choice.

Letters Explained:

"S" model sticks were designed for "street" applications such as drum corps and marching bands. These large sticks were designed for the louder volume and projection needed for these uses.

"B" model sticks were intended for "band" applications such as brass bands and symphonic orchestras. With a smaller circumference than the "S" models, they were easier to control and thus especially popular with beginning drummers. 2Bs continue to be recommended by drum teachers everywhere as perfect starter sticks.

"A" stands for Orchestra. "A" model sticks were designed for big band and dance orchestras. They're smaller in circumference than "B" series sticks and lend themselves to softer playing. These sticks continue to be very popular with many jazz and rock players.

Taper guide:

Short-tapered sticks have a stiffer feel and are more durable, while long, more narrowly tapered sticks are more fragile and flexible with a more delicate sound. The body is main area of the stick, and can be played on the rim for a wooden sidestick sound.

Stick tips:

There are four basic shapes, each with unique tonal qualities, and in a choice of wood or nylon.

Round tips deliver a focused sound that's especially good on cymbals, ranging from the tight ping sound of small round tips to the broader, fuller tones of larger round tips.

Barrel tips have a larger contact area for a broader, more diffuse tone.

Pointed or triangle-tipped sticks produce a focused medium tone.