It's got nothing to do with the model of the WAP of your choice. The main question is what kind of traffic are you going to have.
The traditional Cisco rule-of-thumb is 25 clients per WAP.
However, if you are pushing, say, emails, web browsing, IM's and FB-like traffic then this number may as well go up to 35 clients per WAP.
But if you are going to start pushing HD video then the number is 8 clients per WAP.
Another thing to also consider, if you want to push high bandwidth applications, like HD video for instance, please take note that the 1242 only has 802.11 a/b/g radio and does NOT support 802.11 n and/or ac. This model also has a FastEthernet port.
