Paddle

For paddles there are a LOT of variables.
Type:
Greenland (straight and narrow,) Scoop (the most common,) Canoe paddles, hand paddles, Scooped Greenland…, etc.

Length:
Longer usually means flatter water with faster high end speeds. Shorter means lots of leverage, fast movement, easily flipped side to side, best in whitewater but, blade shapes can change.
Materials: Wood, the traditional. Plastics(often injection moulded,) Composite injection moulded (plastic with fiber reinforcements,) Fiberglass, Carbon, etc. I prefer Carbon but it only saves a few ounces over fiberglass. Fiberglass is more forgiving. Plastics can be good or bad depending…
Shaft:
Metal, wood, carbon, fiberglass, etc… Then you get into bent shafts, feathering, and all that. Ignore it. Choose what is comfortable. But, I would recommend you get used to a moderate feather.

Anyway, the one REI is offering is a good cheaper model. It is HEAVY at 2#6.4. The length can probably be cut down with a grinding wheel if needed, but it is fairly short to start with. It might be a bit long for a packraft, though. It IS a good deal for a usable paddle.

Packrafts can use hand paddles. Think of snow shoes mounted to your hands. They work, but are not real great in whitewater.

PFD's all very. The higher the weight carried by them, the straighter in the water you will be. Currents can change this easily. I use a 15# PFD or about 1/12-1/13 of my body weight. More than enough for me because I don't get excited when my head is near the water line. Some people like more. 1/4-1/5 is about the usable limit. 50# is a LOT of PFD. But, I use a 20# PFD for my 3.5 year old grandson. He can swim, but, not too well…I do not want him to get panicky. And, I make sure the bouyancy is on his chest, not his back. He will float head facing up, not down as with many. This is close to 1:2 for his weight(41 pounds.) It kind'a depends.

The pics you mention are mostly kayak PFDs. These leave you struggling to swim because of the angle the support you at. But, they need that to avoid bunching up with the cockpit. A trade off.

I'd say it does not look like a good paddle. Probably flexy as anything, perhaps fragile, and definitely too long. 230 is good for flatwater, but you'll want to be able to go down to 210 for whitewater. It is cheap, but you'll likely be replacing it soon anyway, so not much savings over an Aquabound. The cheapest Aquabounds are flexy and heavy, but at least you get a totally bomber paddle in return, which is a good idea for a beginning paddler.

Some of those MTI PFDs look perfectly fine. The main issue with cheap PFDs is fit, they'll ride up and chafe your armpits and neck. With an REI return to use there is little risk there. The Dio looks worth trying.

My wife and I bought a couple of paddles along with some $12 vinyl intex "packrafts" and did a couple of trips down the Bitterroot at low water during a summer heatwave

( trip report here:
http://blog.hillmap.com/2013/08/whitewater-in-our-12-packrafts.html
http://blog.hillmap.com/2013/08/day-1-with-our-12-packrafts.html
).

I am not an experienced packrafter though I have spent time in inflatable kayaks, sea kayaks and white water rafts. I would say that this paddle is "fine." Probably not good or great but fine.

The blade's held up to some hard rock hits and it i didn't notice too much flex though the fit between the blade and shaft could be better and i've never used a truly nice paddle.

I did get blisters from the rough fiberglass handle and had to wear gloves on the second trip.

The biggest issue is that it is a sea kayaking paddle intended for low angle paddle strokes. The blades themselves are narrower/longer then a paddle you would want for white water use. This is actually kind of nice for low water stuff as you can make low angle strokes in a few inches of water but a high angle/fatter paddle would probably let you maneuver faster in white water.

The shaft is adjustable in length (and feather able too any angle) from about 225-235 cm which is kind of nice.

Soak the adjustable section of the shaft before you tighten it and don't over tighten or it will be hard to get un done.

If you're paying for an alpaka and/or planing super remote trips, class 3 whitewater or heavy use i'd probably opt for a fatter bladed, proven design or (for flatwater) something much light like trekking pole paddles but if you're just looking to mess about on the cheap and make a few trips a year in mellower water the price is hard to beat.