The odd thing about having a torque wrench is that as you use it regularly you soon develop a sense for the correct torque and you'll find that you don't need it as much. It's fair to say that MOST regular wrench spinners only use their torque wrenches or torque screwdrivers for special applications where things need to be very closely matched or the risk of failure for even a slight over torqueing is high.
That said buying a decent but not top end model will do the job and last you for years if decently cared for. So it's worth buying an OK brand for a little more than the very cheapest imports but I would not suggest going for Snap On or similar high priced stuff simply due to the cost.
The beam style are reputed to work well. The catch is that you need to locate your eyes directly over the needle or the parallax error can result in wildly wrong readings. But on a bicycle this is seldom an issue since they are light enough to reposition the bike so you CAN see directly onto the reading face. But if you ever plan on using it in automotive or motorcycle applications the click style are a LOT more useful. And they don't cost all that much more.