I actually sold my launch day and *mint* iPhone 4 (32 GB) just yesterday here in the Philippines for 10K pesos or $232 equivalent. Should cover most of the cost of a Nexus 4 16 GB. Of course, iPhones cost more here and resell value can still be high for a 3-yr old model. I will miss that iPhone 4 with double the storage but will welcome the Adreno 320 GPU with the Nexus 4. The iPhone 4 simply didnt age as well for me after iOS6 and the fact Subway Surfers, Sonic Dash, Despicable Me: Minion Rush, TURBO, Asphalt 7, etc have terrible lag and frame rates. iPhone 4's GPU just doesnt hold up anymore for many 2012-2013 games.it's a shame the iphone 4's resale value is so low. I can't even cover the cost of this phone.
I would jump into this deal since I have been looking at the N4 as a backup phone even before the price drop. It closely matches my HTC One's dimensions except being a bit shorter but it should still fit into my holster case for my One nicely.
BUT, N4 lacks the durability. I have read too many horror stories of the glass back breaking easier than eggs if the temperature changes or whatever. N4 has a sexy design but I refuse to get another phone with a glass back as iP4/4s has a more durable glass back and still see many owners with cracked backs.
You get what you pay for.
Also where my HTC One lacks like removable battery, memory card slot, and great camera is where Nexus 4 lacks as well. Samsung Galaxy S4 is a better compliment to HTC One and maybe the best Android paired combo at the moment with both matching each other's dimensions just as closely in height and width. It would cost $300 more but One + S4 is more complimentary to each other's weaknesses.
I say to go for the deal just for a backup phone if you had the extra cash and cant afford another 2013 flagship like S4 or One, or just wait for the Nexus 5 announcement. This price cut is really to clear inventory.