well I have only flown early model 337's (non turbo or P) and I never had any problems with either single engine climb, with various loads. The only problem is the well know gear retraction drag brake (which can be fixed with a stc door deletion kit)
I would liken flying a 337 on one engine to flying a 182.
Now of course you'll need to specify if it's the front engine or the rear, beause the performance is different for each. That said, what kind of single engine ceiling have you been at gross weight with an engine out? If you're limping home close to sea level with no significant terrain beneath, perhaps it's okay.
It's certainly not akin to flying a 182. Among other things, with the 182, I've regularly dropped loads of skydivers out at 15,000 feet and higher...something you'll not being doing on one engine in the 0-2/337. In fact, even at low altitudes, you won't meet the same rate of climb on one engine as a 182...and one one engine you're in an emergency condition in the 337, whereas you're perfectly fine in the 182. Furthermore, lose the remaining engine in the 337, you shouldn't count on fairing nearly as well with the subequent forced landing as you will with the 182 when it's powerplant fails.
and if you dont like not having a driver door, best avoid flying most pipers or anything larger
Well, presently if I want to get out of the cockpit, it's either leave the seat, retire to the rear supernumary area and descend a flight of stairs to the main deck before leaving the main entrance door, or exiting the top hatch out of the cockpit and descending on an emergency cable about 38' to the ground. And no, I don't like not having a driver door. My other regular airplane has ejectable doors and quck release side panels, a full steel roll cage, and I usually wear nomex, gloves, boots, and a helmet.
The cherokee doors are a disgraceful joke and it applies from the PA-28 through the Seneca. It's a sorrowful piece of engineering.
However, seeing as you mentioned it, when I flew the Navajo, I had an exit door in the cockpit. It's a little bigger than a Cherokee, and it's still a piper. The Cheyennes we flew didn't have the door, but we figured we could plow over the station operator in back if we had to get out in a hurry
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