My skepticism hairs are standing up.  Supposedly Ford gears, but Ford hasn't made gears for the 8" in decades.  Something's off there.

Its a decent package.  3.25:1 is a good ratio for a T5 depending on tire size.  I run a 3.50:1, and am quite happy with it.  Runs 75-80 on the highway without issue and at reasonable engine RPM. 

My advice on any rear end parts is buy based on quality, not cost.  Avoid Richmond gears, they tend to make noise while coasting, even when set up properly.  My personal preference is for Yukon gears.  I've installed many sets of them and have never had a single issue.  They set up well, are quiet, and I have several sets with thousands of miles on them and not a hint of any kind of issue.  I recently had a set of Ford Motorsports gears for an 8.8 that had a machining error and the yoke was so tight on the splines I couldn't get it to seat.  I bought a set of Yukons and had the rear set up in a couple hours.

The Traction Lock diff is decent if you're not running a bunch of power through it.  If you are, they don't last too well.  Yukon also makes great limited slips.  Auburn is another good manufacturer if they offer one for the 8". 

For bearings, just stick with a good manufacturer.  I would consider the following all on par in terms of quality: Timken (USA), Koyo (Japan), and SKF (Germany).  Bearings are not where you want to save money.  The cheap ones have tolerances that are too wide and are made from lackluster materials.  The easiest way to set up a rear is to make some setup bearings for the pinion.  Grind out the ID so you get a slip fit with a second pair of bearings.  This is where tolerances come into play, if the bearings are quality the actual bearings you use and the setup bearings will pattern exactly the same.  If they aren't they won't, and you'll be ripping it back apart again, pressing off bearings, etc. because your pattern isn't right. 

In general, there are some good deals on eBay, but you need to be wary.  A LOT of stuff on eBay is knock off China made junk, often even coming in knock off packaging that looks authentic.  There is no real recourse when stuff goes sideways due to international laws which do not hold Chinese companies accountable for stealing IP from others in spite of patents, etc.  You may or may not be able to get your money back even if there's outright fraud.  I'm not saying don't buy stuff off eBay, I do it all the time, I'm just saying be careful.  Positive reviews are a good way to check, but those can be faked too.  Look for incorrect word use, improper grammer, etc. that would seem to indicate the person writing the reviews is either the same person or aren't native English speakers.  I know, its sad that it comes to this, but that's the world we now live in. 

The item specifics list brand as QP which is probably Quick Performance. They are stating that it fits a Ford 8" rear end.

I vote YES! it would be worth it. When you 'show-off' for the crew........you wanna leave two stripes of smok'in-molten melted rubber!  Its worth it for the neck snap-ability (is that a word?) of the added traction when you stomp-the-crap out of the accelerator.
I guess
6s6

I like my Currie limited slip in my 8” with 3.25’s.
Originally installed with a c4.
Recently installed t5 (3.35 first), might step up to 3.55 in the future.
Don’t miss the open diff at all.
Look at cost of doing it multiple times.
Can add up fast.
You’ll still enjoy it no matter how ya do it.