For the longest time I've been using Omron's upper arm-strap monitor. It's quite cumbersome doing this alone since I only have 2 hands. So I looked into the wrist monitor and wanted to try it out.
I purchased the Omron 7 series wrist monitor from Walgreens. Priced at $59.99. Positioning is important. You strap it to your wrist and put your arm against your chest so that it can get your HR. It has indicators to let you know if you're positioned properly, otherwise it won't pump. Super easy to use.
Readings were acceptable when compared to the manual monitor at the doctors office, and the public monitor at CVS. It stores up to 100 recent readings for 2 people, and a guest setting that doesn't store results.
Tracks heart rate and indicates an irregular beat. Mine is always showing irregular so it's certainly reading properly.
Austinite Approved.
Here's a video a guy did that demonstrates how easy it is to use...