Hey there! I totally get why you're feeling overwhelmed - choosing your first PLC for a packaging machine can be daunting with all these big names. Based on my research, here are the 3 most critical criteria that will save you from future headaches:

1. Local Support & Expertise Availability - This is HUGE for beginners. Check if there are local technicians, programmers, or service providers in your area who know the specific PLC brand. Allen-Bradley dominates North America (40%+ market share there), while Siemens leads globally (35-40% share). If you can't find local help when something goes wrong at 2 AM, you'll regret your choice.

2. Programming Software & Learning Curve - Allen-Bradley's Studio 5000 is considered more intuitive (40-80 hour learning curve), while Siemens TIA Portal is more complex (60-120 hours). Mitsubishi's software falls somewhere in between. As a beginner, you want software that won't make you pull your hair out when you're trying to troubleshoot or make simple changes.

3. Future Scalability & Communication Protocols - Even for a 'simple' packaging machine, think ahead. Will you need to add sensors, connect to HMIs, or integrate with other equipment? Check what communication protocols each PLC supports and how easy it is to expand I/O points. The S7-1200 supports up to 1231 I/O, FX5U up to 384, and CompactLogix up to 4096 - but you probably won't need anywhere near those numbers for a simple machine.

Bonus tip: Consider the total cost of ownership, not just the sticker price. That includes software licenses (which can cost thousands), training time, and maintenance costs. For a simple packaging machine, you might not need the most powerful option - sometimes simpler is better when you're starting out!