Your goal seems to be wanting data as you ride. And your budget is limited. The 200 sounds like it's just the ticket. While you can't really measure heart rate without a HRM, you can do a decent job of estimating cadence by counting revolutions over a 30 second window. What's interesting about tracking your rides is you can compare the same ride over a period of time and conditions. Having accurate elevation stats don't matter for such comparisons.