Till now 35xx series can fully use unlocked maps, Monterra and Oregon 6xx too.
Newer devices have protection. Unlocked maps (any) don't work in 2014 Nuvi devices, no unlocker available.
Actually only 1 new nuvi exception: nuvi 4695R / 4592R / 4590,
like in Gpsmap 64 and Edge 1000, maps can be unlocked by new gimgunlock 0.03+MapSigPatch but Unicode maps needs some dirty tricks anyway.
Some 2013/14 Nuvi devices require downgrading firmware, if available, to use unlocked maps.