Tony:

My smallest Magnum of the XL or XLS series is a 0.40 engine. I do have a plain bearing Magnum 0.25 that isn't quite old enought to vote, but it's getting there.

The twin I'm building for the 0.25 engines is not getting a pair of Magnums, but that's because I got a pair of zero time HB 0.25s for the price of one Magnum - if they are a problem Magnum engines will go in their place. And if that happens the Magnums will probably get the Perry carbs from the HB engines. Just as I like the Magnum engines, I'm also a strong fan of Perry carbs.

Sum up: I would have no worry in buying the Magnum engines of whatever size I needed.

Bill.