ORIGINAL: bigedmustafa
As long as you don't mind spending the money, there's really no reason to buy anything other than O.S. Max.
O.S. Max makes a huge variety of glow engines for almost every conceivable application. Their quality is excellent, their power output is very good relative to other brands, and O.S. Max isn't the most expensive option on the market.
There are a lot of great values out there, and a lot of lesser known brands offer power and reliability for less, but you'll never be disappointed by choosing O.S. Max.
I was a little on the fence again about what engine to buy; did a search and this old thread came up, my first engine purchase
This time I was between a Super Tigre G-51 and a 55AX (almost double the price) for my Venus 40; the 46AX just isn't enough for me on that plane. This last comment is steering me toward old faithful...
I really would love to save some money, but there's just something about strapping an engine to a plane and seeing it in the air after one tank of fuel!