those are 2 very good IDPs. Beason is just starting off slow and Thomas Davis (his counter part at LB) is snatching up alot of the tackles. Give it some time Beason is a beast, he will start generating some valuable points for you.
Way I look at my IDPs is the exact some way you would for your offense, best matchup. So for your LBs you want to pick a matchup that should produce a fairly good amount of runs against them, I.E. a Minnesota type running first team. For DBs its complete opposite, your looking for a pass first team that way your guys will be involved in more plays, I.E. New Orleans type team. I also take into account the offense that my IDP plays for and look for one of 2 offenses. One would be a terrible offense (why Kirk Morrison is so valuable) because they will see the field a heck of a lot more then a team that the offense grinds out long drive after long drive, thus limiting the action the IDPs see (great in real life football, poor in fantasy ball). The 2nd type offense would be one like New Orleans, where they have a ton of quick hitting plays through the air, thus bringing the defense out onto the field more.
IDPs are fun to play with, but can at times make you pull your hair out because one week they may go for 15 total tackles, 1 sack, 1 fumble recovery and an INT and then the next week go for 2 total tackles and a pass defended. Its just playing the best matchups you can possibly play to give your IDP the most field time to be able to rack up Tackles, Sacks, INTs or Pass Defendeds.
Thats about the best way I can describe how I play IDPs, others may have a different opinion, but quite frankly it comes down to 2 things. 1. the talent level of your IDPs, which equals fulltime PT which you have in Beason and Morrison. 2. how much time the player sees the field, because he can be the best tackler in the league but if take for example last night Miami's D was only out on the field for what just over 15 minutes? Thats going to hurt an IDP's value because they aren't seeing enough plays to get their noses into.
Hope this helps!
A big thanks to deluxe_247 for the sweet sig!