I say Tena is a lot better than depends. Here are some differences.
Absorbancy/holding: Most depends can hold 1 or 2 wettings but they're not built for #2. Most of the tenas that I've seen can hold up to 3 wettings and can withstand a pile of crap. D:0/T:1.
Tapes: Only 2 depend products utilizes tapes, and they suck. AU is better used when the sides have been ripped open, and FMP tapes barely last a single night. Tena tapes are more reliable and stronger. The Classic brief tapes occasionally rip only when putting one on, while other products may come with adhesives and a landing zone. D:0/T:2.
Sizing: I have a 42-in waist and weigh 250 lbs. For most Depend products, I can fit in both sizes. Tena has their sizing wrong, I'll stick to the classic briefs for this one. The mediums say up to 47-in, but I can't close the tapes, however the large ones say 48-59 inches and those fit me all snugly. D:1/T:2.
Pricing/Availability: Getting Depends online is too expensive. To buy one pack of adjustable underwear, it's $15 at any store that sells incon products, and whenever I shop for them, I'm always afraid I might run into someone I know. Tena, on the other hand has varied prices, but where I live, they can only be bought online. I found the best deal for them on EBay: A case of 100 classic briefs for $36 on medium and $44 on large. D:1/T:3.
Comfort: Depends only use a small portion for padding, most of them just feel like spandex on my butt. Tena uses more care for people with bowel issues, as they have more padding and the wings feel soft. D:1/T:4
I used to like depends until I got my first case of Tenas. I think Tena is a far superior brand.