I have built up and logged some insane hard miles on a number of suicide hubs and never had a failure and still use one wheel that has seen over 10,000 km...

Biggest issue with suicide hubs is when they aren't built up properly and removing a worn cog is really difficult and can destroy the threads on the hub if one is not really cautious especially if it was one I put together.

You can get a decent rear fixed wheel for very little money and if you are a skidder this is the way to go as a suicide hub should only go on a braked bike.

Since I am always swapping cogs I only use my old rear wheel as part of a spare set for my coaster bike as it has the same size cog and wheel swaps are pretty easy.