You said RSlogix5 and PLC-5 which is an older systems being phased out by most companies.
The Logix 50000 (ControlLogix and CompactLogix) is the system to which most people are migrating, but there is no free software so the cost for a training platform is a high entry barrier.
The MicroLogix controller and the RSLogix Micro software is still a very good platform on which to learn. Lots of people are using them and the basics translate to the 5000. Best of all, the cost is very low. The software is free and you can pick up MicroLogix controllers on the cheap.
If you can get someone to pay the cost of the 5000 software and a piece of hardware then definitely go for it. If not, stick with the Micro.
OG