This seems to be basically a collector that sends data to Datalog (a NON open-source service that costs $15/host/month). I recommend setting up Grahite+statsd (it's truly amazing and open-source realtime metrics setup).
Pup has a narrower scope than Graphite (which we also use and love), but optimizes for shortest time to app metrics viz.
(Oh and Datadog itself is all free up to 5 hosts - but remains completely optional)
I'm not sure I understand what "shortest time to app metrics viz" means. Are you referring to the time Pup takes to create charts? Or the lowest time frequency (minutes, seconds etc.) it can handle?
Graphite defaults to reporting at 1-minute intervals, and can report at a finer granularity (1 sec. intervals) if you tweak a few settings and set up a cluster. I'm just wondering how Pup differs in this respect.
By default, pup aggregates statsd data in 10s intervals, and the UI refreshes it continuously.