I read about the ALO-modified HFI-780, and it looked like a good value. But, I wanted to know if I basically liked the sound of the unmodded HFI-780 first. So, I bought a stock HFI-780 from ALO, and used them for 2-3 weeks. I found that I really liked their sound, including a prominent, but really beautiful high end (it reminded me a lot of the ER4S treble, which I also enjoy tremendously). I thought that, with more refinement and a quieter background, the real beauty of which these phones were capable would come out. So, I sent them back to ALO for the mods. When they came back modded, they were everything I was hoping for - the full (but not wild) bass, with lush, tuneful mids and a treble that surpassed that of the ER4S, to my ear. I received them almost two years ago now, and these phones are still in my collection of four most-valued full-sized phones: an ALO-modded (woodied and recabled) SR225, an HD650 with an 18 AWG ALO Jenna cryo wire replacement cable, a stock HF-2, and the ALO-780. My favorite amp with the ALO-780 is a Mapletree Ear+ HD fitted with NOS tubes. Was the $$$ spent on the ALO mods to the stock HFI-780 worth it to me? Every penny. Instead of having a set of phones where I'd hear what they were doing really well, and wish that their flaws were not there to limit their goodness, I had a set of phones which were finally freed from those flaws to do really exceptionally what they had previously done "only" really well. The final cost of the ALO-780, including two shippings, was about on par with the cost of the HD650 + aftermarket cable, and the modded/re-cabled SR225. And, I'd put the overall sound quality of these three sets of phones on a pretty comparable level as well. So, during the time period over which I was collecting those three headphones, the cost of the modded HFI-780 was in the range of costs for which that level of sound quality was selling for. The HF-2 is an outlier (costing about 2/3 to half of what I paid for the various other three phones - it's a really nice "thank you" gift from John Grado orchestrated through Todd the Vinyl Junkie). So, if you're looking for a full-sized closed phone with the gorgeous upper end of the ER4S, the modded HFI-780 is a good pick, in my opinion - having used the ER4S on a daily basis for two-to-three years. Good shopping!