Perhaps just personal preference, but I like the groove that Nightforce and EGW put down the centerline of their rails.
I don't see that in the pictures of Seekins and have no experience with their products.
Nightforce puts a lip on theirs behind the front seating area. Supposedly that helps absorb recoil. But, it's pretty useless unless you bed it since it's not custom machined for your rifle and must therefore allow some tolerance.
I have seen some cheaply made rails that I would not use. But, NF, Leupold, EGW are all quality products. Seekins also looks good on their website, but I've had no first hand experience with them.
I like the 6 cap screws on the Burris XTR rings. I feel you can get a good even grip without straining. I have not tried any other picatinny rings.
Also, take a look at what Michael Eichele had to say about bedding the base:
new custom cant get to shoot
I've never had that problem. But, some have.
If you pay attention to your install, I think you'll be pleased with any of the ones discussed.