You need to decide what's more important to you. The university which "blew Lancaster out of the water in terms of facilities and lecturer engagement" or the one where you won't risk feel "living in the shadow" University of Manchester.
Given that neither university offers Electrical Engineering, would I be right in assuming that you mean Electronic and Electrical Engineering (EEE)?
In terms of both "the quality of the courses" and "networking and employment opportunities", the data are all over the place, unfortunately.

According to the National Student Survey, 91% of Electrical and Electronic Engineering BSc students at MMU were satisfied, overall, with the course. The number of Lancaster is just 68%. That might tend to align with your "blew Lancaster out of the water" comment. As might the degree classifications. According to the Higher Education Statistics Agency, 97% of graduates from that course at MMU gained a 2:1 or above, which is impressive given the typical A level grades of students there are DCC. At Lancaster, the typical grades are much higher at ABB, but only 88% get a 2:1 or above. So based upon those two comparisons, and your own offer-holder day experiences, MMU would appear to win on "the quality of the course" race.
However, you also asked about "networking and employment opportunities". For metrics in that area, Lancaster wins. According to the Destinations of Leavers from Higher Education Survey, sixth months having graduated 75% of Lancaster graduates are "Engineering professionals" earning an average of £28,0000 annually. MMU graduate are "Engineering professionals" 29% of the time, with an average annual salary of £23,000. (Also, 15% of MMU EEE BSc graduate are "Sales assistants and retail cashiers" sixth months after having graduated.

)
If we roll forward five years and look at median earnings, using the Longitudinal Educational Outcomes dataset, Lancaster EEE graduates are earning £37,000 compared to MMU EEE graduates at 33,000.
The only explanations I can come-up with for the stark differences here, are that maybe Lancaster has a much better careers service and is much better are helping you find a job upon graduation. Or perhaps MMU graduates are always being compared to UoM graduates.
It seems to me that you should choose MMU (as it's a "better" course) but take personal responsibility for the subsequent career, and do so sooner rather than later (i.e. not just when graduation is around the corner).
All of the above data can be found on
The Uni Guide. Data relevant to these courses in particular can be found at:
•
Electronic and Electrical Engineering at Lancaster University
• Electrical and Electronic Engineering at Manchester Metropolitan University