You really need to pick an aircraft for what you intend to do 80% of the time. It is rare to find that turboheliamphibianjet that will do everything for you. Comparing a Maule and a 180/185 is not exactly a fair comparison as they are rather different aircraft. The 180/185 comparison is mainly $$$ and load. If your shopping in the early market, then the price difference narrows. In the later market the gap in price widens as does the effective load.
For me, it is a perfect fit with a 185, I can tank it up full and really not worry about overloading it. The biggest thing I tend to carry are bikes. I liked my first 185 due to it's stretcher door. Made bike transport a snap. It is more of a PIA in my current model, but float models are worth more.
I've seen 180's with a 550 on them and the price was very reasonable. You still lose some load capability, a 470 equipped 180 will be slightly more economical, but thats really splitting hairs. The 185 has a strengthened tail. I only recently learned that it has more internal structure than the 180's, which can get a bit of a diagonal crease, but I do believe the later models ended up with the same internals for production ease.
It really boils down to budget and how much you really intend to do. In my case, my family would rather be skinned and dipped in lemon juice, than fly. Somehow the boys ended up with their mother's sensitivity to motion. So my passengers end up being confined to me, my bikes and any thrill seeking friends who won't puke all over my panel. It wasn't just the 185 that caused my lads issues, the Birddog did, Caravan did, the 206 did as well as the Chieftain. So I would test my kids and wife on a few trips before I made my final decision on what kind of aircraft you should buy, if flying them around is your intention. If it is just you, then figure out what you normally expect to take with you, weigh it, figure the range you need and see which model will do it. Add about 20% to what you weigh out, you'll always end up taking more.
BTW,
I would never buy any plane based on if it can be repaired with duct tape. I have had the doors ripped off by a bear on the NOAA UH-1H/205 helicopter and still flew it out. You can fly some really f*cked up airplanes if you have to. My Canadian buddies talk of pee patches on old fabric aircraft in the Arctic. Get a rip on a surface, cut the patch out, pee on it. Lay it on the rip, let it freeze solid. Apparently works just fine. I just couldn't figure why they insisted on peeing on it, rather than just pouring some water on it from a bottle???


don't know exactly why... it just does.