The thread's original question "what is your favourite sidearm" - but I wonder, "favorite for what purpose?" Duty carry vs off-duty, CCW vs target shooting; two-legged targets vs four-legged targets . . .?
My Munchkin sized Kahr PM 40 is a great companion when I'm walking late night downtown. My ancient Colt 1911 .45 ACP fits my hand and eye without conscious thought and carries enough "oomph" to put a man down nearly anywhere my round winds up on his body. My SIG 226 9mm complied with a contract requirement, and gave me an endless supply of "free" ammo. My S&W .44 Mag Mountain Gun with handloads gives me some sense of protection when I'm strolling Alaska's rivers in the company of big Brownies. What's my favorite sidearm? The tool depends on the terrain and the target, oh, and the bank account, of course.