It is a revelation, being out from under the Verizon contract, no longer needing a Verizon Network Extender to receive service in my home. Straight Talk with ATT sim is working great, all of it.
My old GN's each had KIT KAT Shiny Rom on them,(Rooted, unlocked since new with various older Shiny Rom derivations) they worked well and the new Nexus 5 was not unfamiliar.
I sold both my Samsung Galaxy Nexus , without sims, on Swappa, for a net of $100 each. The new owners gave me excellent positive feedback.
I would recommend anyone who signs up with Straight Talk to use the APN settings they provide and wait at least 5 days for MMS messaging to work correctly. Once it did it's been great.