We have 3 Nextfits and I like them, but the harness adjuster (especially for lower headrest settings) isn't as smooth as I'd like. However, it has another 2" of seat depth over the other two. My son RF in it until 4yo and never looked cramped (more a comfort issue than a safety issue of course, but he might have complained and demanded to FF sooner in a seat with less legroom). The high sides of the seat can be a little difficult to work with, though a little after 2 my son started climbing in on his own in our CR-V so it became less of a nuisance. Both installation options for the NF are very easy.
If I was choosing a different seat, I'd probably get the 4ever if I could get a good deal on it (many got them for ~$140 at Target over thanksgiving weekend!). The only feature it's missing in my book is a lock-off, but otherwise it looks like a very nice option and, at the right price, a great value. My BIL got one and said that the harness adjuster is easier than the Nextfit. Just keep in mind the shallower seat pan (same goes for the Milestone).
The Blvd looks very nice, but it's a pricey seat and I've heard of quite a few people having difficulty with the CT panel. Obviously you're not supposed to use LATCH, but those who do use it don't like the hooks.
ETA: check your target for 4ever. Many people bought online on BF but might start returning to stores. Online returns are often marked down dramatically!
ETA2: If you're looking to buy online, probably the cheapest place to buy is Albee. It's a reputable shop with b&m locations in NY. Free shipping, no sales tax for you. Nextfit and Milestone are both $240 using coupon JAN20.
http://myaccount.albeebaby.com/mod_referralRewards/welcome.php?referralCode=RFRHXL