.....just converted from the Archer, which I've been flying (mostly UK and close Europe touring) for a couple of years, back to the 172 - reason being that the Club have a couple of brand-new 172SP's on the hire fleet.
Liked the Archer, and agree with most of the comments made here - very benign (perhaps a bit too benign?) but easy to fly and safe.
The lure of the new 172's was too great, though (what with 180hp fuel-injected engines, moving-map GPS, complex autopilot etc) but what I've found is that the 172 needs to be "flown" (which probably isn't a bad thing) much more assertively, especially during approach & landing - the Archer would virtually land itself if set up on a stable approach.
Other comments on the 172SP - love the grey metal panel (looks like a proper aeroplane!), the sturdy new seats (from the Caravan, I believe), proper inertia-reel seatbelts (for all 4 seats)....and the quiet!