The Seneca 1 was comically underpowered - it makes almost any other twin (including the Seneca 2 and after) look like a Mach 3 rocket ship. On the other hand, if it is there and available, and you are just doing the rating, it's a twin.
I was checked out in a Seneca 1 when I had logged plenty of time in other twins, including Cessna 310, Duchess, and Baron. My checkout was in the southern USA, and although we were near sea level, the outside air temperature was 90F. With just myself in the left seat, and an experienced Seneca 1 pilot on the right, (no payload) we set off down the runway, both engines at full power. With what felt like a mile of concrete behind us, it only just staggered into the air. It was quite clear to me that something was horribly wrong, so with a good chunk of runway still in front, I started to close the throttles to abandon the takeoff. My colleague on the right was cracking up with laughter at the terror in my eyes: "No man", he said, "this is it! This is as good as it gets!" And so it was that we climbed into the hot sunshine, on both engines, at about 200 fpm.
At least the Seneca 1 will teach you why a piston twin is NOT a performance A aircraft.
If you are going to rent a twin to travel around in, take another look at that Duchess. Similar systems to the Seneca 1, but an infinitely nicer aircraft.