I have used Caldwell, Harris, Atlas and Evolution bipods. I had an Atlas but lost it.
I'm currently using a Harris HBRS and have a hard time justifying the $300+ price tag of other bipods.
Caldwell - Don't waste your time
Atlas - Great bipod. Very strong and stable. I like that the legs are deployed from the top instead of the bottom. Really have to crank on the knob to lock in the swivel function. I would recommend the CAL model with the lever. They make leg extensions but I have not used them so don't know how stable they are. If you have a swivel stud, you need an adapter or have to install a picatinny rail.
Evolution - Great bipod and lightweight. Swivel locks down easily. I like that you can buy longer legs and just swap them out. Not a fan of deploying the legs from the bottom. Almost becomes a 2 handed job. If you have a swivel stud, you need an adapter or have to install a picatinny rail.
Harris - It just works. It does what the others do but less glamorous. Definitely need a lever for the swivel lock. Need an QD adapter if you are using a rail. With both of those options you are still 1/2 the price of the other bipods.
If you are dead set on spending the extra $$$, I give the Atlas CAL a slight nod over the Evolution just because of how the legs are extended but that is my personal opinion.