I have a hard time giving advice like this because i'm not a typical knife owner/user. I tend to only buy and carry knives that i won't be afraid of really using, and some knives are just too **** nice and beautiful for me to feel good about laying into them.
I had a Sage 1, and it was on par with the nicest knives i've ever handled. That knife was flawless and so gorgeous, i just couldn't see myself using it and scratching it up and dropping it and all those bad things that happen to EDC knives, so i traded it in on another knife.
The only knife i have that has gotten around this rule is my Caly 3 ZDP, because i already used it and the 420J2 outer layer scratches so easy, i wouldn't get much for it on a trade in and honestly i just love it too much to part with it, so i dedicated this one to dress/holiday/special occasion carry only.
Every other knife i have gets used at one point or another and i have no guilty feeling about abusing the hell out of them if necessary (and by abuse i mean within reasonable knife use, not using them as screwdrivers). Besides the Caly 3, the other knives I have are a Para 1, Para 2, Delica 4 ZDP, Centofante 4, Native SE, and a Ladybug H1 SE hawkbill.
The Ladybug is my key chain knife, which is basically just a backup knife. I'd also use it if i had some kind of spyderedge/hawkbill task that it may do better with than my PE knives.
The Cento 4 i bought because i love wharnies. This knife doubles as another dress/casual EDC and doesn't get used as much as my others, simply because i prefer the others.
The Delica 4 ZDP, i had been carrying religiously until i got the Para 1. This knife was an internet deal at $50 and was my second go at ZDP. I bought this because 1) everyone needs a Delica, 2) i wanted another go at ZDP without risking edge damage to my Caly 3, and 3) it was a great buy. It gets carried when i just want a change from the Paras. It's also my son's "learner knife" until i get him his own Delica (shhh, don't tell him! lol)
The Para 1, this was my first experience with compression locks, as well as my first experience with G10. I have grown to LOVE and prefer both. This knife was borderline holy grail for me just a few days after carrying it. It would still be my primary EDC if not for the next knife...
The Para 2, i got because 1) HYPE, 2) I trust Spyderco and their dedication to constantly improving even the best things, so surely there had to be something better about it, 3) I wear khakis at work and the digicam blends in with them nicely (custom tan G10 is in the future). Initially i wasn't impressed the first time i handled the 2..at least not enough to justify buying a knife that was so similar to one that i already owned. Now that i own it, i'm very satisfied. I like the option of the 4 way clip but i still prefer tip down for this knife, i love that the exposed spine/tang is gone, i love the longer/taller thumb ramp, and i love the larger more comfortable choil. Amazingly enough, i had the owner of the shop weigh both Paras and the 2 came in at .2 grams more than the 1, which is damned impressive to me considering 1/2 inch more blade and full skeletonized nested liners. Overall i have to give Spyderco an A+ for the refinements of this knife and i'd be crazy not to recommend it.
I also had a Manix 2, which was an awesome knife but i just didn't love it. I did like the ball bearing lock and how amazingly smooth the opening/closing was on that knife...it easily takes the cake as the smoothest knife i've ever opened, with the Sage 1 taking a very close second and my Para 1/2 following. I would still have the Manix except it got traded in on the Para. I liked the steel better on the Para, the ergos better, and the lighter package better. Overall i would definitely recommend any of the knives i own.
SHARPEN IT LIKE YOU LOVE IT, USE IT LIKE YOU HATE IT