Unless your area is PACKED with systems of EQUAL interest to listen to, why would one put multiple trunking systems in the same bank anyway? While this is technically possible, why would you want to? And, mixing a 460 mHz system with an 800 is, well, I don't think that will work any way. At least with a Uniden scanner you can NOT do that and be able to listen to them both.
Save yourself the hassels and program them in SEPARATE banks. It'll be much easier to zero in on something should you need to get to a specific talkgroup in a hurry anyway.