They are pretty nice. Get very hot. All depends on how much you plan to use it. But compared to regular wood they are probably a little cheaper since they are more efficient. And cleaner. Less ash to remove..
I do remember a few years back, there was a pellet shortage in my area, and all the stores were out.. I suppose you could burn regular wood in one if necessary.
Around here pellets are about $5 for a 40 pound bag and one bag will last 2 to 3 days if the stove is on all day. I got home from Surf and Turf Sunday night and my wife had the down stairs of our house at 80 degrees and the stove was only running at medium.
I have a Whitfield in my shop, and I love the thing. I'd say it's pretty comparable in price to a woodstove if you have to buy your wood. In my barn/woodshop I like my wood stove though to burn scraps.
Everyone I have known that owned one was happy. But if wood is cheap where you are that could be a better option. For me forest service wood permits are $10 per cord. Much cheaper than buying pellets but lots of hard work involved. If your going to buy your consumables then pellets are the way to go. Assuming you have a local supplier.
This year I bought a pallet of ECO Bricks for my wood stove. They are like really big pellets. Burn all night. So I kind of use both.