I own Triple Fi 10 Pros. They are not identical, in driver design, to the UE 4 Pro. The Triple Fi 10 Pro is a three-driver design while the UE 4 Pro is dual. When UE speaks of the UE 4 Pro as "the Poor Man's UE 10," all it's really saying is that the UE 4 Pro is the lowest-priced product in the Custom series. For $400 - the same price you'd pay for a Triple Fi 10 Pro - you can have a "custom fit" UE 4. But while the "custom fit" is definitely an advantage, the driver in a UE 4 is not as good as the driver in a Triple Fi 10 Pro.
If it were, they wouldn't call it a UE 4 Pro and charge you $400. They'd call it a UE 10 Pro and charge you $900.
The key hint is in the description of the SuperFi 5 Pro, which says, "The SuperFi 5pro has the same sonic signature as our custom personal monitors. It is perfect for emerging musicians or for consumers who want to listen like a pro."
It has "the same sonic signature" as their "custom personal monitors?" Which ones, do you think? I'll give you three guesses; the first two don't count.
"Housed within the universal body are two individual speakers and an integrated passive crossover circuit board that directs the low-end frequencies to a dedicated speaker for bass and the high and mid-range frequencies to a dedicated speaker for treble."
Why, isn't that the same design as the UE 4 Pro?
"Inside each custom earpiece you’ll find our proprietary dual-armature speaker system. In addition, an integrated passive crossover circuit directs the low-end frequencies to a dedicated speaker for bass and mids, and the high frequencies to a speaker dedicated for treble. The result is reference-quality, evenly balanced frequency response."
Truth be told, the real "poor man's UE 10 Pro" is the Triple Fi 10 Pro. You get the same drivers for $500 less. What you don't get is a "custom fit." I'm not here to suggest that a custom fit isn't worth having, because everybody who has gotten the fit has spoken highly of it. But if you can find the right tips to make the Triple Fi 10 Pro work, you've got one heck of a IEM for a fraction of the cost of a UE 10 Pro.
I know because I own one. When I first put it on, I was disappointed in the sound, which seemed tinny. I had to play mix and match with the tips. One complication is that the Triple Fi 10 Pro sports a sound tube (for lack of a better term) that is unconventionally large. You can't use regular-sized tips with this IEM, not unless you bore a bigger hole. This makes finding the right tip more of an adventure than with other IEMs. But anybody who wants to save $500 can get awfully creative in a hurry. I prefer foam over rubber, so modded some foam Comply tips to serve my needs (wide but not particularly deep earholes).
Sorry guys. I'm not forking out the other $500 anytime soon. And if I can make it work, anybody can.