I bought the Maverick ET-7 dual probe wireless model and have been very pleased with it. Reviews at Amazon and here seem to indicate that digital therms are not the most reliable group of home appliances ever devised, but I consider my $40 well spent. I've checked mine with boiling water and it is dead on accurate.
http://www.crazysaver.com/mav-et7.html Polder and Sunbeam are two other names that seem to come up with positive, model specific, reviews.