Any advice for a hardtail for trail/fire road/mining trail riding...with progression...

I have test rode (and liked):
a) GF Tassajara (no discs)
b) Diamondback Topanga Comp Disc
c) Kona Blast (no discs - but is upgradeable)

I am planning to test:
d) Giant Rainier (discs) - sale @ LBS
e) Raleigh M80 (discs) - 2005 model
f) Iron Horse Warrior Comp (discs)

Is the Raleigh M80 essentially the same as the DB Topanga? What are the differences I should be aware of?

I am not up on all of the componentry and quality issues, but from my research the above appear to me to be similar offerings...except maybe the Rainier has upgraded components compared to the others...?