MOTM

>>>>
What's the difference between the 148 and 149 other then one is 
cermet? Why choose one over the other, if they are the same value 
wouldn't they operate the same?
<<<<

Cermet = more expensive, more temp stable. Use for critical 
applications where drift is important, like VCO Coarse and Fine pots.
 
>>>>
Paul tends to use Spectrol when mounting to the PC and then tends to 
use the Bourns for non-mounted, coincidence or is there a science to 
selecting pots?
<<<<
 
Sometimes it has more to do with mechanical issues than anything 
else. I can't speak for Paul, but my experience is that it's easier 
to get the Spectrols with the pc mount lugs than the Bournes. So 
sometimes you end up using cermet when the circuit might not strictly 
call for the added stability.

>>>>
For my MiniWave I used Spectrol 149's and they work just fine.
I'm 
about to order 149's for my Dark Star, should I maybe put more 
thought into this or go with Dave' recommended Bourns? Or does it 
boil down to cost since the Spectrol's cost a little more?
<<<<

Either will work fine. You don't need the extra performance of a 
cermet pot in this application. I used Bournes on mine. Actually, 
since you are mounting pots off-board for the refit, solder lugs is 
the better way to go. I don't know if you can get the Spectrols with 
that style or not.

Moe