I like the Milwaukee 101 and 102 units for their combination of reasonable price and durability. They both use the SE220 probe that is a gel-filled, double-junction pH probe that has proven to be durable and reliable. The gel-filled unit is well-suited to storing in a 1M to 3M KCl solution and that is what I do. My current probe is over 4 years old and shows no sign of aging, but it will someday. With that eventuality, the BNC-type connector means that I can easily select any manufacturers BNC style probe and it will work with my meter. The probe is about half the cost of a new meter and probe, so its worth it.
A probe is useless unless its calibrated and you are sure its reading correctly. Get pH 4 and pH 7 solutions, so that you can make sure the unit is reading correctly. Pour small amounts of each solution into separate containers (bottle cap, shot glass, etc) and check the meter response. Rinse the probe with DI water and blow and/or blot all excess water off before inserting into the next solution. Throw the used solutions away. You can't reuse the solution or return them to their bottles. On top of that, the solutions have limited lifespans and should be replaced about every year.
While I encourage brewers to obtain pH meters for brewery use since they help fine tune and resolve brewing, I also recognize that this is a pricey piece of equipment. Using a program like Bru'n Water helps improve brewing when that equipment is not available, but using both does help you better fine tune your brewing.
You can read more about pH meters and brewing chemistry related topics on the Bru'n Water Facebook page.