hrm fitness watch for women

[kieran]

my wife, Johanna, has set herself a target of a sprint tri later this year so i was going to get her a hrm fitness watch thingy - can anyone recommend or give warning about various models - main concern is size of watch face. ideal would be something like the Garmin forerunner 50 ( with foot pod and cadence sensor) ? But is this too large? Anyother ideas?

Is a foot pod a useful feature for runners?