I've flown an experimental to Europe. I wrote an article about the trip for the December Kitplane magazine. You might find some of the information useful.

With planning those trips can be achieved. You need to think in terms of IFR equipment levels, range of 800nm plus reserve. Standard insurance stops at the US and adjacent border countries and can be difficult to obtain if you want to travel further.

The cost of those trips can be considerably more than the cost of travelling the same distance in domestic territory.

Canada, Mexico and the Caribbean are routinely flown by experimentals with few constraints, but be prepared for a lot of effort and expense to go beyond there.