Oh boy this thread is rather... interesting...
I love both companies and they both have a lot to offer, but here's what I'm noticing at least from Blade this year: the lack of prototypes from Benchmade. When I was at the Spyderco booth, the most disheartening thing aside from no photography is that I can't take home any of the prototypes. I don't know if it's just me, but I just wish Benchmade would do more collaborations and pump out some new designs.
Variety: Spyderco is a company that is just on top of it's game for what it has to offer. I don't know of any other knife company that offers so many variety of knives for so many different situations with so many different steel types. We have to give Spyderco credit for providing such variety for us.
Thumb hole/stud: I love Spyderco thumb holes. People don't appreciate thumb holes until they have to wear gloves or put a ziptie through the thumb hole. Being able to wave just about any Spyderco knife is pretty awesome. Even though it's a small thing, having thumb holes does take weight off the knife as opposed to thumb studs which adds weight. My favorite knife by Benchmade is the 746. Thumb holes just work remarkably well.
Locks: Honestly, if I have to do a task where I'm worried about lock failure of any degree I reach for a fixed blade not a folder. Are we all forgetting that folders are meant for cutting, not chopping, batoning, prying or any of the ridiculous criteria that people have. I love Axis lock. It's fun and reliable. However, like any mechanism the chance of failure increases with each additional part. That's why I prefer simplicity of compression lock or even just lock backs. Keep things simple, less things to go wrong.
Blade Steel: Spyderco just offers so many different steel types that I wish I have the money to get every single Spyderco variety out there. I wished that Benchmade had offered more steel type variety without stepping into the Gold Class. I think it defeats the purpose of high end steels by putting them in collector pieces than users. That's why Spyderco earns my respect in this area because it's considering the biggest factor: the user. Sure Spyderco has a lot of sprint runs, but I won't feel as bad that I messed up my <insert color> G-10 than a really exotic wood or beautifully anodized titanium. At very least, I'm a huge fan of 154CM so BM is still keeping me happy.
Quality Control: Benchmade is slipping quite a bit on this. I bought two Mini-Grips as gifts and when I had inspected them they were very off center and have a lot of blade play. When I tighten everything, the blade is immobile. oi... I also had recently sent back a 482 because the blade grind was very uneven and the centering is absolutely horrible. The grind was bad enough that BM had to let me know that they had to replace the blade because of the extreme of one of the bad grinds. When they send my knife bad, the blade grind on the new blade is still uneven so I had to send it back into BM. With Spyderco, the fit and finish on them are just perfect if not near perfect. I do get a few bad ones on there, but it was a Centofante. The centering on it is bad and the fit and finish isn't as good as my Delica, Superleaf, Southard, or PM2. Centering on a pinned knife wouldn't be that great in the first place. The centering on my PM2 isn't perfect either, but it's plenty far from the liners so I don't really care. Aside from those two knives, all my other Spydercos are just perfect.
Customer Service: I think Benchmade definitely has an edge in this one. I've bothered them so many times and they just catered to my needs. I'm so grateful for such wonderful customer service. The wonderful customer service of BM is one of the reasons why I love buying Benchmades. I know if I end up getting a lemon, Benchmade will make that lemon into lemonade. I've only had a few contacts with Spyderco customer service. I appreciated the limited help that I had received. I thought that my Southard needed new cup-washers, and Spyderco is unable to provide any extra parts for any foreign made knives. The rep did send me PB bushings to see if they are adequate. I appreciate the effort that she provided despite how it didn't remedied the situation, but trying is better than just saying they can't do anything.
Overseas vs USA: I love USA made products as much as the folks before me and the folks after me, but I accept the fact that great knives are made all over the world. USA isn't the only country in the world that makes knives or quality knives. For the defenders of BM saying that their oversea models shows in prices where Spyderco doesn't, well... have you seen a oversea BM that has anything better than 440C or Aus8. I don't believe that I've ever seen an overseas BM with ATS-34, D2, or S30V. When I look at some of the Taiwan Spydercos guess what do I see: CTS-204P,CPM-M4, S30V, and CTS-XHP. Steels aside, have you seen the fit and finish on those overseas BMs? Some of the HK line are so sorry that I couldn't believe that Benchmade had released them. Spyderco certainly has overseas factories, but the quality is maintained even with the budget line knives. If the knives produced there are good then the knives are good regardless of their origins.
As much as I love both companies, despite how I have more of a bias toward Spyderco I'll still buy the Benchmades that'll catch my eye.