Is anyone using these and finding that it has slowed the device down, and caused hangs or crashes?

Since I’ve started using segments, I’ve notice that browsing screens on the device is slower, I’ve had the device hang and switch off a couple of times, including once when riding and I passed the start of a segment that I was not going up, it started beeping, then hung with the beep continuing, and then switched off. Luckily when I switched it back on my ride was still there and I could just press start again.

Should I be looking at the 520 as newer hardware to cope with running segments, or is this a common issue on both?

its not an issue I’ve seen on my 520.

Anyone with a 510 having problems too?

Haven’t had any issues with my 510. The only problem with mine is not being able to work out how to compare me against myself rather than the QOM!