Whoa, hold'er there a minute.
Let's consider something:
85db + 60w = 102.7db
87.5db sensitivity + 60w = 105.2db
85db + 105w = 105.2db
87.5db + 95w = 107.2db
85db sensitivitiy + 170w = 107.2db
Heat is never your friend. the less power you're using, the better IMO - i really doubt the scanspeak has double the heatsinking capability... it uses roughly a similar size voice coil for starters. I think a woofer rated for 60w being fed more than its rating, is a lot more likely to last longer than a woofer rated for 170w but being fed twice the power at its rating.
Now as a general rule you have to remember the nature of music content. Unless it's heavily compressed, 60w RMS is something like 250w peaks, and somewhere in between those two points more closely approximates the nature of non test tone content IMHO.
A raw power handling number doesn't necessarily approximate what we hear (the audible effects of compression), or if it even matters. Test tone ratings are one thing, but I think real world application is a whole nothing thing. Sometimes these are determined by free air mechanical limitations rather than thermal limitations too.
Check out this article by Paul Apollonio:
Loudspeakers & Power Ratings Part III: The Test Results — Reviews and News from Audioholics
given the limited passband with a subwoofer (60hz to 800hz) combined with the actual nature of music content, I can't imagine being scared to blow a woofer, unless you're listening really damn loud to undynamic content. In that case I don't really see any of the Phils as the optimal choice, as that's not what they're designed for.