Use the right tools for the right job. If all I'm doing is putting together new code, then one monitor is fine. If I'm debugging, porting code or troubleshoot

Use the right tools for the right job. If all I'm doing is putting together new code, then one monitor is fine. If I'm debugging, porting code or troubleshooting an oncall emergency then multiple monitors is better. Also, on a Mac I can more easily get away with one big monitor however on a PC I must have at least 2 monitors to feel ok. Of course, YMMV.