Pick and choose, definitely. A smattering of spidey thrown in and then the ML stuff I like. Toy Biz has convinced me to never, ever rush into buying a toy again.
Here's what I have:Wave I
Captain America
Iron Man
Iron Man Gold CHASE VARIANT
Wave II
Doctor Doom
The Thing
Doctor Doom Doombot CHASE VARIANT
Hulk with Shirt Variant
Wave III
Wolverine (Yellow and Blue)
Magneto - both original and box set release - happy to unload one

Thor
Wave IV
Gambit - from box set
Beast - from box set
Elektra - both red and white
Goliath with Antman and Wasp CHASE FIGURE - thanks Scott
Wave V
Sabertooth
Colossus
Silver Surfer
Red Skull CHASE FIGURE
Best of Marvel Legends Wal-Mart Exclusives
Thing Trenchcoat
Stealth Armor Iron Man
Here's what I plan to getWave VI
Phoenix (green/yellow)
Dark Phoenix (red/gold) CHASE VARIANT
Deadpool/Doop
Wolverine (Brown/Yellow)
Juggernaut
Wave VII
Hawkeye
Apocalypse
Vision
Wave VIII
Doctor Octopus
Captain America (Ultimate) - maybe
Storm
Ice Man
I also have from the box set Rogue and the no mask wolverine.
From spiderman I have the following:
Ultimate Rhino
black spiderman - later version
Hobgoblin - a must have
Green Goblin - would have passed if I'd known about the S6 set
Venom - ditto
Carnage
Suprisingly I have few of the original spiderman figures from the line. I have the original red Daredevil and the yellow chase version, but have only the spiderman that hangs from the gargoyle. Would like the red and black and would still like the red and blue spidey, but I suspect I will be satisfied with the S6 version. From the movies I have two spideys, super poseable and the movie green goblin.
As for the FF box set, I'm waiting to see if there is an Amazon sale a la the Urban Legends box and the X-men box. If there is, great, I'll snag it, but if not, no loss. As for the regular releases of Namor and Human Torch, well, there are so many on the pegs here that someday they'll have to clearance them, hopefully at a much more reasonable price ( they reg at $12.99 here).
I managed to pass on the Urban Legends box set mostly because I already have the white Elektra already. I'm not a huge punisher fan and didn't care to get yet another spidey. All of the daredevil's I've seen in that box are painted much, much better (albeit differently) than the daredevil released in the later spiderman classic wave (same wave as Kraven?). The Amazon price is fantastic, but I just didn't need more DD or spidey figs.
I also picked up the Mr. Fixit Hulk and the Absorbing Man figures from the Hulk line of recently. Both are great, I'd like to pick up an Abomination too, but can live without it. Smart Hulk is tempting too, but these Hulk figures are far superior, IMO, to either the early ML or the movie line (where's the puking icon?).
My must haves:
Mr. Fixit Hulk
Elektra - either version would do
Thor - spectacular
Wolverine yellow version, personal fave
Hobgoblin - just a spectacular figure, great articulation and super sculpt
Colossus - wow.
Captain America from series one is an honorable mention but I feel both he and Ironman are too small in terms of scale. I just don't perceive Wolverine being the same height. I do love the Cap figure though as it is classic. Though it nees the Red Skull to complement it completely. Stoopid chase from buffoons at Toy Biz.