What do you plan to use it for? If its any help, we have built 3 engines with a $20 harbor freight torque whrench, although there is no guarantee it super accurate. For normal stuff I would say the summit brand should be fine. If you're doing internal stuff, Rods, mains, even heads, you might want to make sure you are using an accurate wrench.
when it comes to precision instruments use what the pros use,sur buy your sockets,wrenches,screw drivers from them,when you slam your hand in to a block or fender somewhere,no big deal.that'll heal up,but when you tweak your block,or a rocker stud/rod bolt backs out/off,you can bet on your torqe wrench as the culprit,i personaly use snap-on
instrument.or at the very least...........craftsman.we're talking torque wrenches here not sledge hammers.
When it comes to something like a torque wrench don't scrimp just to save a few bucks, drop a cheap one once and the calibration is history if it was ever even close, spend your money on a quality tool made by a known quality company that you can contact if their ever are problems
And, cheap or expensive, make sure you have the calibration checked. I recently found a new Craftsman torque wrench on evilbay for $45, Sears sells it for $75. Checked the calibration and it was dead on. You can find deals if you shop around.
Look in the phone book for a meterology lab, the kind of place that cals meters etc: most can do torque wrenches, can also be done with a Skidmore but if your not in the steel business they are hard to come by