Are the US engines any good?

I think US Engines were rebadged Quadras. Good, reliable engines that have been out of production for many years, They have been supplanted by a number of more powerful engines built for model use (adapted from industrial engines). If you have one, use it. If you are contemplating buying, consider that parts may no longer be available.

Thanks; I have one that I was going to use on a 1/4 scale Swift. Seeing that this airplane was designed around 40 to 50cc engine with a mag I thought that it would be right for the CG.

Good reliable bullet proof engines.

Good engines. My US 41 can be a bit hard starting first time out for the day but strong and reliable.

The US engines started in NY state but after the company was bought they were built right here in PA !
They were built as a clone to the Quadra engines so a US 41 is very similar to a Quadra 42. I have both US and Quadras and they are engines that start easily and run for ever. A bit heavy compared to today's chicom engines but perfect for scale planes and warbirds. They made 32,35,41,42,57cc engines. Most magneto but a few electronic.
Here was their latest website: http://www.usqaero.com/index.html

Some more history on the company who bought US engines

I have this in another thread but I was wondering if there is a Carb for the Q35 that has a choke? Something that Walbro makes that could be a direct swap. I really want a choke. not sure I awill be able to reach the carb on my new plane to finger it, as per the SOP on these engines.