The best replacement for s100 is s110.

The best alternatives to s100 are rated as following:
★★★★★  s110
★★★  p21s
★★★  g12
★★★  sx260
★★★  lx7
★★★  s95
★★  g15
★★  s120
★★  g1x
★★  sx40
★★  rx100
★  g16
★  lx5
★  hx20v
★  sx280
★  sas6ir
★  hv40
★  sony rx100
★  p330
★  x10
★  bike brite
★  nikon p300
★  hf200
★  300 hs
★  panasonic lx5
  canon s95
  s95 canon
  s110 canon
  j1
  panasonic dmc lx5
  tz20
  canon s110
  qtek s110
  canon sx260
  lumix lx5
  xz-1
  nikon p310
  ixus 510hs
  nikon j1

Your alternative for s100 is not listed? Suggest!
Speaking about s100, one probably shouldn't forget about sony rx100.

Other search terms related to s100 and their ratings are:
★★★★★ sony rx100
You have in mind a companion for s100 and it is not yet here? Propose!



Google Trends

Scale is based on the average worldwide traffic of s100 in all years. Click on graph for more.
s100
s110
p21s