I’ve had both expensive custom ones and the 30$ Cabelas ones. IMO there are benefits to both.
The custom ones will look the best and don’t fade in the sun easily. Most of them are really durable as well as hold up to wet dogs and such. Only downside is a little harder to put on and take off if you want to wash them.
The universal ones are nice for how cheap they are. The Cabelas ones I’ve used are kind of a semi-custom fit. They look decent and hug the seat nicely. They are a little easier to install and take off to wash. They do fade easier though, but if you get 2-3 years out of a set, another 60$ to replace them isn’t a bad deal.
I personally like the fit and look of the custom ones better, so that’s what I have on my current truck. They have held up for 2 years of little kids and dogs so far, still fit and look like new.