aaron
When I started flying early 1980s a C150 was £19 per hour
A domestic fridge was not a lot more so every trip was almost the cost of a fridge for the house
I really do not think there will be a lot in it between the two so you need to look at what is the most cost effective way of achieving your goals?
Unless you intend to knock up 200 hrs PA i would not look at outright ownership of an aircraft.
work out how many hours you need to fly and my guess is your best way will be to approach a private owner and rent those hours or look at a non equity shareholding.
Ownership outright or part is fraught with stumbling blocks which will balance out over the years if that is your intention but renting although on paper more expensive per hour means you can walk away and you will know what your costs will be.
Ownership outright or shares always holds a question mark in costs and it is not so easy to turn that capital outlay back into cash without a hit!
So if you are intending to keep the aircraft for a few years then look at ownership if its purely hour building then buy the hours you need.
unless you can buy one at such a snip that you can easily sell at a profit when the time comes to dispose of the aircraft (unlikely)
Preference between the two? C150 !!! Never liked the terror hawk
Pace
Addendum
looking at SmartHawkes suggestion below I would seriously have a chat with the company he supplied a link to then fly at low cruise settings and learn to lean correctly to cut your fuel burn and reduce your fuel costs