I'll be in North Jersey...
Are there any sources as to how the coverage is in those areas?
I live in North NJ - between the Parkway and the Turnpike up near Route 3.
I have not dropped a single call on my iPhone 4S since I bought it in mid January.
Speed is obviously slower than 4G devices but this is a PHONE issue, not a carrier issue. While some people may state that previous studies show that Sprint has a lower speed compared to others, might I remind you that it's truly unlimited. I'd much rather not have to worry about data caps and take an extra second or two to download a page compared to paying an extra $20-30 per month in data overages. Don't forget if you have Cablevision (Optimum) for your cable or internet provider you get access to the thousands of Optimumwifi hotspots all over the area.
Plans are great. We're on the Everything Family 1500 plan. 1500 Shared Minutes between the account, unlimited nights and weekends, unlimited mobile to ANY carrier mobile, unlimited texts, and unlimited data. Can't beat this bundle for the price.
So, don't feed the trolls on here and just try it. I think they have a 14-day money-back guarantee program, but just remember that even if you return the device and cancel the account in the 14 days, you won't get a refund on your initial activation fee unless you return it within 3 days.
As for call quality I've found that my quality had improved when I moved from Verizon to Sprint a few years ago, but this could also just be the technology of the phones themselves. I also noticed a stellar improvement upgrading from my BB Curve to my iPhone 4S. I also think there's an old news article on Macrumors that actually said that Sprint has the best either receive or transmit voice quality, one of the two, and came in 2nd or 3rd out of the big 4 carriers for the other one.
I will add this one caviat: I've heard (but not experienced) some of my friends and family on Sprint having a "Dead Zone" near Giants Stadium. I'm not sure if this is solely affecting Sprint, or just random. I personally haven't experienced it, but I usually don't drive in that direction very often, and I know when I went to a few football games last year I was able to text and upload pictures without any problems - and that was on my Blackberry. The iPhone is a considerably more "usable" device.