I switched from 81 Lamar to 83 JB and I like him much, much more. On field you can really only feel his lower mobility if you scramble, but the normal moving around the pocket feels the same to me. His accuracy was a marked improvement. The stat difference is lower on the 83 versus the 81 so I'm not sure how much of a difference you might experience, but for me using the 81 I could definitely feel it. There's still the occasional goofball, but it's not a consistent issue like Lamar seemed to have.
If you can pick JB up for cheap, I'd say do it. Try him out and see how you like him. Worst case is you feel no difference and you just resell him. Best case, he's a significant improvement over Lamar and you've got a better QB that'll give you less headaches and make playing a bit more fun.
I switched from 81 Lamar to 83 JB and I like him much, much more. On field you can really only feel his lower mobility if you scramble, but the normal moving around the pocket feels the same to me. His accuracy was a marked improvement. The stat difference is lower on the 83 versus the 81 so I'm not sure how much of a difference you might experience, but for me using the 81 I could definitely feel it. There's still the occasional goofball, but it's not a consistent issue like Lamar seemed to have.
If you can pick JB up for cheap, I'd say do it. Try him out and see how you like him. Worst case is you feel no difference and you just resell him. Best case, he's a significant improvement over Lamar and you've got a better QB that'll give you less headaches and make playing a bit more fun.