[Elecraft] K1-4 last band (15/17) choice help

[David Toepfer]

I'm looking for advice/experince again.  I don't really work much on either 17
or 15, so I would like some advice.  The best unsolicited advice has said:

1) There is a lot of local activity (depending on your locality) on 17 on SSB. 
Can the same be said about CW?
2) 15m is an excellent DX band when it is open.  Is it open often enough to
justify dedicating 1/4 of the band capability of the K1-4 to?

David, K3TUE
.