Thanks for all the replies. The weight is probably the limiting factor, as a 360 is around 330 and a 540 is over 400 (
60297-21[1].pdf (lycoming.com)) There is still ample time to decide on an engine, and I would like to get a little more familiar with what others are doing. There are more than a few Zeniths flying with Viking engines, and I will certainly be looking in to that. I will also be thinking a lot more about Aeromomentum. The next project build will probably be electric or hybrid. That said, traditional engines such as the 360 are certainly a good option, have their merits, have their drawbacks, and are plentiful, if not overly priced. We'll see.
I looked at several certificated aircraft, and would still consider buying one. But nearly every plane I looked at, I found myself thinking "I really like a lot about this, except for ******* (fill in any various gripes)". If I am building my airplane I can build it any way I want, and if there is something I don't like I can either blame myself, or fix it. Add to that, with any used airplane, it may fly great, run great, and have good logs...but there is no way to know what's hidden.
I have worked in military aviation for going on 25 years, and have worked with several great, and some not so great, mechanics, both military and civilian. I have worked with many AP/IAs that I would trust with my life, and I have also worked with many AP/IAs that I wouldn't let them put gas in my car. What I have learned over the years is that if you really no kidding want something done right, and know without a doubt that it is done right, you have to do it yourself. I then have someone I trust look over my work. I do not get offended by someone watching over my shoulder...I welcome it.
This thread (and a couple others) is probably what pushed me to go the experimental route.
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