The best replacement for 1.5 is 1.6 rockers.

The best alternatives to 1.5 are rated as following:
★★★★★  1.6 rockers
★★★  1.65 ram
★★  2 way diff
★★  1.25 curling iron
★★  1.6 rocker arms
★  3t mri
★  1.35 volt ram
★  1.6 roller rockers
★  1.35 ram
★  1.6
★  1.65 ddr3
★  1.65
★  1.4
  3 tesla mri
  2.1
  3.0 sata
  2.71
  10 mbps
  1.6 ratio rockers
  opengl 2.0
  sata 3.0
  1.8 prius
  2 way lsd
  dodaf 2.0
  2.1 android

Your alternative for 1.5 is not listed? Suggest!
Speaking about 1.5, one probably shouldn't forget about php 5.3.

Other search terms related to 1.5 and their ratings are:
★★★★★ php 5.3
You have in mind a companion for 1.5 and it is not yet here? Propose!



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1.5
1.6 rockers
1.65 ram