What services have you used and recommend for profiling and debugging PHP applications in production? Blackfire, Tideways, something else?

I run a number of production servers and would like to aggregate profiling/benchmarking data, function call graphs, etc. It seems the top PHP offerings are Blackfire and Tideways, and am wondering if I should choose one over the other for any reason. They both support unlimited machines, which I haven’t been able to find in non-PHP specific offerings, such as New Relic.

It would be nice to have a service that also saves front-end javascript error stack traces, but I haven’t been able to find one that A) provides as much detail on the PHP side of things, and B) doesn’t cost a fortune.