for a castle 1406 in a slash, the lowest kv option would be best suited IMHO.
1410 would be a better choice, but the sc-401 v2 should out perform even it.
mmp is a great esc with tons of available power - until you try to power a high power servo off of it. unless you're planning on running on the edge of insanity with 5s or 6s power or running a sensored motor, the WP- SC8 or tenshock/toro equivalent ESCs should keep right up with it and allow the use of a decent servo at a much lower price point.
program card will be a serious plus to have with any of the esc's. many consider them necessities since push button programming consisting of flashes and beeps really is a downer to an otherwise good day.
the velineon is okay, i guess. has a handful of shortcomings and not ideal for a heavy SCT, IMO, but will get the job done if you're looking for an uber simple something to just putz around with. personally, i'd pay someone to solder if i had to to get something a bit better.
JANG said
Basically most of the world wants MMPs with BECs that don't suck

deerhurst said
Overkill is under rated!!!!