i had a flowmaster 40 on my 92 s10...fell OFF after 3 months hahah..overall..it was a bit too..hmm..well wasnt throaty enough for me..so i just cut it all the way off haha. the brackets and everything were crappily put on..i had that on when it was still running with a 4.3L though..when i put a 5.7L into it i used thrush welded...which i still like to this day..

i may try magnaflow for my f150 just because i dont like how my friends flowmasters sound on his bronco..

 

Have a megnaflow super turbo on my 3v v10 sounds good but quieter than I was wanting, should have gone with the plain strait though turbo. Was looking at a flowmaster 44 delta but nobody nearby sells them.

 

I have a Magnaflow on my 86' K10 with a small block and a flowmaster 40 on my 03' SD with the 5.4L. Both are single outlet exhaust like the factory made them. I can honestly say the magnaflow is so quiet that I cannot hear it while driving. I don't like that at all. The flowmaster is louder on initial startup and while getting into the throttle but isn't droning inside the cab at all. In fact i can't hear it unless i have the windows in the back rolled down. I prefer the flowmaster for sound but the magnaflow for robust construction. Either way you cant go wrong but the magnaflow IS QUIETER than the flowmaster.

 

You also have a super-duty, presumably with the stock cat still on, you could run without a muffler and it would be quiet.

 

Tried that first sounded good but way loud with lots of after fire poping (3v v10) still thinking about a 44 dela flow.

 

I took 2 Flowmasters off my 97 f150 & put a Magnaflow dido with the xpipe in the muffler on it. It stopped the drone & sounded very good. It seemed to give more power too but I didn't dyno it so I can't prove it

 

On my 89 F250 (with a 351w, manifolds, factory down-piping and home made piping including the Y pipe back) we put a Flowmaster 50 series, si-so 3" on it. And the muffler came off of a relatives truck that had the muffler on it for the past 15 years. It's got a mean rumble at idle, but not real loud. On acceleration if you really lug it out it growls up to about 3000 rpms and then its a real loud bark after that. And if you get on it immediately it barks but it never has a crackle or pop. I find it to be pleasantly loud when I want it to be loud, but it's still not too obnoxious in town.
I recently invested in a set of headers and true dual exhaust with 2, 3" si-so, Summit Street and Strip mufflers which are identical to the Flowmaster 40 series for 1/2 the price. I'm sure that a lot of the difference is the true duals with all 3" piping, but it is a LOT louder when you get on it, but it still has a meaner, little more crackly, idle. I've never had Flowmaster mufflers drone like a lot of people say they do though. I don't have any experience personally with Magnaflow though. I've got a friend with a foxbody mustang with a stroked 302 in it that has dual magnaflows that sounds pretty good, but it isn't my favorite sounding vehicle.

 

Personally, I like the MagnaFlow over the FlowMasters for several reasons, the reason is the straight threw design over baffles, as the baffles will break free and rattle like crazy. I can't remember how many I've replace for that reason.

 

The magnaflows flow much better. Mine with the built in x pipe seemed to help my performance. It didn't have the flowmaster drone at highway speeds. It sounded better to me under acceleration. It made my 5.4 sound like a Mustang GT. I will never buy another Flowmaster. I don't like the sound.