These bags are of very good quality and very functional. Easy to adjust to your racks and the ability to move foward or backward when mounting. I've used them on a couple of bike camping trips with no issues what so ever.
Better yet, Western Bike Works always has great sales and excellent customer service.
This top tube bag is very well made had very light. I bought a regular (small) size for use on shorter top tube dropbar bikes, so it doesn't get in the way too much when stopping and standing over the bike. It has enough room for a regular size iphone 6 (definitely not long enough for the PLUS ones), a wallet, and maybe two energy bars. The main issue I have is that the bottom strap interferes with the same brand frame bags I have... I have three Apidura Backcountry frame bags, one full frame in small size, two half frame ones in small and medium, and they ALL have the same issue... Maybe it won't have the same issue with the extended (long) version of the top tube bag, or if your frame bag allows you to move around the top straps. By the way, Apidura's Expedition line frame bags do allow different positions for the top straps, but I tend to go with the Backcountry line for the light weight.
Perfect size to carry your oh **** kit. Love the mounting system for under the saddle, easy on and off. It works on all three of my bikes, but didn't work on my husband's, but I think that is an anomaly. The reflective patch is a nice touch too.
After 3 years of daily use the pannier is only suitable for use in dry weather (holes forming at corners and folds). Not a bad run, I bought a new set to use in the rain.