Corsair 128GB Voyager Slider X1 USB 3.0 Flash Drive, Speed Up to 130MB/s (CMFSL3X1-128GB)

Pros: size, both physical and capacity. 256GB in a USB drive that's not much bigger (smaller in some cases) than drives with much lower capacity.

Cons: It isn't the fastest drive out there, I ran a couple benchmark but the numbers are nothing to write home about. The drive is plenty fast to watch full HD movies from but copying to it can take a bit depending on file size.

Overall Review: I know benchmarks are great for comparing, but real world results for me tend to be 45 seconds per gig for writing files. Most videos I write to this drive range between 3.5 to 7GB so it can take a few minutes per video but it's worth having the ability to transport them in my pocket.
My benchmarks don't seem to be quite as high as some other reviews but I'll post my results anyway. Comparing mine to other benchmarks, your speeds may be closer to theirs than I'm getting.

My equipment is:

MB: Z97E-ITX/ac
CPU: i7 4790k
RAM: 16gb (2x8) 2133
HD: Transcend MTS400 256GB M.2 SSD
OS: Windows 10 Pro Insider Preview build 10074

CrystalDiskMark 4.0.3
4K: read 6.922 - write 0.078
Seq: read 43.84 - write 24.30

I have to give this thing 5 eggs. It may not be the fastest thing out there but it has made my life much easier. When copying multiple videos/large file you'll have to give yourself a few extra minutes but that's been the case with all portable drives I've encountered anyway.

Pros: Large capacity. Shipped fast.

Cons: I am disappointed with the transfer rates I'm getting. I have encrypted it using LUKS w/ ext4 file system. Maybe it is not designed to be encrypted though I have other flash drives ( 8gb, 4 gb, 2 gb all different brands) using same encryption and file system that transfer files faster. This is a problem for me since the whole reason I got this was to be able to hold considerable amount of data and if I can not encrypt the data (do to performance hit) it that make this drive useless to me. I don't know if it is simple because of the large capacity or if it is not designed to be encrypted but either way I think I will have to return this flash drive. Other c/o the thickness of the drive preventing them from using other usb port next it but I did not have this problem. I did notice that the sleeve that you pull back to expose the usb port tends to partially close while inserting into port even when you ensure that you have securely snapped it completely open exposing the usb port on the drive (if that makes sense).

Overall Review: Gets hot while transferring large amount of data to it.