I can't decide. The DS-2CD2132-I is cheaper than the DS-2CD2132-I - $125 vs DS-2CD2532F-I - $185 and better specwise ie 3 times the ir distance so logic says go with the DS-2CD2132-I.
But...the DS-2CD2532F-I looks to be really small in size thus less intrusive/ideal for a home installation...