Originally posted by Spaceman Spiff
Hmmm you hear statements like this a lot on RCU, but most of the time the person saying it knows nothing about the person he acuses of this. if you hear conflicting statements about a particular engine, it is far more likely the company has quality control problems, than the person writing a post, cant read. besides, some of the instructions even from the most reputable companies are flawed. OS for example wants you to break in engines sopping rich and cold for several minutes, almost everyone who has been around for more than a week agrees this is not a smart thing to do. question everything you read, there is always some complicating factor, unrealistic expectations littel real experience, quality control problems, there is always somthing limiting the view of the person writting, except my posts of course! 
another thought, you almost never run into anyone complaining about an Irvine, Obviously irvine owners ae better readers! LOL!
I have not found any quality control problems with Fox, they do need a long break in, especially older ones, but a couple of newer
Fox's broke in rather quickly. They also have had some carb design quirks but that is solved now. In fact the Fox .60 was the best .60 engine in the MAN shoot out.
There are a lot of myth's out there even amongst knowledgeable modlers, one of them is that OS is top quality and Fox is the worst. IMO Fox has better quality control than OS but some of the carb design is not as refined, however they work fine. I have a Fox Eagle I .60 that they quit making in the late 70's. I bought it with a Perry carb because I was told that Fox carbs were crap. I quit the hobby for 15 years before actually using this engine. When bench running I couldn't get the engine to run right. High end was all the way out and idle was practly at full lean, still wouldn't transition well. Well doing some horse trading I ran into a period Fox carb and bolted it on. It ran great ! I only had to adjust the high end I didn't have to touch the idle. Runs at 12,500 RPM with 5% nitro. This is better than my K&B .61 of the same period! Pretty good even today condidering its just a cross flow baffled piston engine.
The Fox .46 is much more powerfull than the OS FX .46, but you may want to buy a seperate muffler, the Fox muffler is too loud.
Don't buy the OS FX .46, my favorite knocking around .46 sized engine is a TT .46, its slightly more poweful and a lot less expensive, and maybe a bit more reliable. IMO only a few OS engines are worth the price. The 1.6 FX for example.
Also hobbsy is probably one of the most knowledgeable posters on this board. I don't dissagree with him very often.