i've only used a troller once on a 14 foot alumium. 4 adults in it and it moved surprisingly even though it was only a 30lb thrust. that was a rental at orangeville reservoir. i think the V shaped hull is what made it go. cuts through water nicely.
my own boat is an inflatable. soft bottom with 30lb troller. it definitely does not move as fast but it's comfortable for me. i need an inflatable because it's always in my trunk and i fish where i am on the road. plus once a week during summer i go straight to lake or river from work and so i can't haul a boat on trailer.
since you have 55lb, you will definitely be moving faster than me but let me tell you, you always gotta check the wind forecast. even with a 55lb on a flat bottom, that wind can push you around if it's 30kmh. with an aluminum you will cut through the water.
and i troll all the time. sometimes for 3 hours in the river. and i will always troll between spots on a lake. i either put the rod in the rod holder or between my legs next to my "other rod". with the aluminum you can probably troll faster and so it makes it less tedious.
and i made a floor for me to stand on. this makes fishing way easier. for casting and trolling. so keep that in mind to see if the zodiac comes with a fold up floor.
and consider how much fishing you will do and where. like i mentioned above, my boat is portable and goes where i go. i could do not do that with a trailer boat or even a car topper.
and if it's a big alumium, and a car topper, you will have to use some ingenuity to handle it by yourself. and once you have a trailered boat, you have to consider the extra cost of paying to launch at many lakes, whereas for hand launch boats like inflatables and canoes and yaks, you either pay less or launch for free. and many small lakes don't even have ramps for trailers.
and also remember, motors can break while you're on the water. and if it's windy, and you have a flat bottom, good luck rowing back to shore by yourself. that's why i always have two extra drive/shear pins with me for the motor and also a socket wrench to take the prop off and replace the pin.
there are dozens of reasons to choose either of your options. ideally you could have both!
blow up boat for small waters and take wherever you go. and aluminum for bigger lakes in windier conditions with more people on board with more room and ability to bounce off rocks and stumps and branches and not care.
the sevylor seahawk 4 can be bought from walmart for $120 and that's what i have. modified it though. and you also need a motor mount which you might find online for like $50. plus you need a car powered pump for it which i bought years ago for $15 but probably cost $40. given the relatively low cost, it would not break the bank to have this in addition to an aluminum. but once you get into the better brands then it can be many hundreds.
i myself am thinking of a car topper like a plastic jon boat so i can use that closer to home and still load and unload by myself. about $600 on sale at CT. but then i'd need a $200 roof rack too.
anyway, any questions about inflatables let me know and i'll share some of my other experiences.
