Well, it is basically a Twin Arrow :-) (For its target, that’s likely a good thing, not a bad one – the Arrow, while not particularly exciting, isn’t too demanding of the owner).
Because of the better payload and reduced fuel consumption the 1 has around 33% better fuel economy per seat passenger than the later version.
Businesses that measure capability by bottom line would recognise this utility.
One last benefit it is sub 2T without an STC
….though it is a struggle to get to IFR levels, so that point may be moot 
>>Well, it is basically a Twin Arrow :-)
If anything a twin Saratoga. At lest that is eher the cell is from. The twin Arrow would be the Seminole
Just had a look on the W&B of the seneca 1, that has actually the advantage of having 4 places + 2 crew, that would be definitely an advantage over the twin comanche.
But you can’t really load 6 people. with an average empty weignt of 1.3t, 180kg fuel (50 usg) and 4×70kg pob, you are a 1.8t, 100kg from the limit. So you can take a fifth one or some luggages, but not a 6th. I mean you can if you are stretching the limits, but with a light twin, it’s a domain where safety is less ensured…
So for 4 people + luggage, twin comanche is lighter, go fast and consume less.
With the seneca V, you can take a 5th either beside the pilot but not in the rear, unless you add with 40kg in the nose, and you are mtow.
The Seneca I hast 93 USG fuel capacity which means 253 kgs . With that about 300 kgs full fuel payload remains. Pretty much 4 adults without bags.
Fuel flow at 65% is about 18 mph so with 45 mins reserve about 4 hours. Accodring POH it will do 150 kt at that setting and optimum level so that means 550 NM taking into account climb and so on.
The 2 in comparison with the same fuel flow will do about 160 kt but has 123 USG usable. That translates into 6 hours and 900 nm in similar conditions. With the 1999 kg stc it has a full fuel payload of 310 kgs. And if you are in a hurry it will run 170 kt.
For me, the 2 is hugely better than the 1.
The 1 will climb to FL090 in around fifteen minutes, not a homesick angel but quite respectable.
The turbocharged versions at FL90 produce KTAS153-159 at 28in 2200 RPM and 22-24 usgph. So unless you want to inflict cannulae on your passengers the speed advantage is modest for a big jump in consumption and maintenance.
One minor pub quiz factoid is that Piper initially envisaged the Seneca 1 as a three engined type, with the third engine in the nose Junckers JU52 style!
So much has been said about twins that they are now largely regarded as “evil machines” by potential aircraft owners. At the end of the day, it’s just an aluminium tube with 2 engines bolted on. Someone needs to buy that Baron
