Twin pros and cons
You usually have two of everything on a twin. Two alternators, two fuel pumps, etc. Hopefully, and more importantly, two vacuum pumps. In other words, double the worries. Bad fuel in a twin and you lose both engines. The average light twin glides like a rock. You can always install an auxilary vacuum pump on a single
A big misconception about a light twin is more safety. Notwithstanding twin-engine operation concerns, e.g. flight near Vmc, losing an engine means you buy time to maneuver for safe off-field landing, if you're not near an airport. I remember how we practiced engine-out procedures in our Seminoles at ERAU-Prescott. It was amazing how quickly we lost altitude. Of course, bad technique made it worse.
Lose one on takeoff and maybe you can struggle up to altitude to fly a full pattern to land. On a hot day, you may again get more time for that off-airport landing.
Speed depends on the airplane. I recall that an A36 Bonanza cruised almost as fast as a Seminole. I also recall that our retractable Skylanes had a high cruising speed.
Even with the possibility of losing two of everything, the percentages of that are remote. I'd say a lot depends on the mission, but, you're probably safer in a twin that is operated safely and properly.