Before hand I want to remark that I have done hours of research, browsed through endless benchmark pages yet still don't feel confident enough to make a proper decision and I have to make the decision very very quickly as I have a few shows coming. Thanks for understanding and sorry if my question is a bit dull and noobish. It's about buying a new laptop obviously.
To sum up quickly; I will be using two Macbook Pros for the show, one for for the audio, one for the visuals obviously. I already have one but planning to buy this as the second;
https://www.amazon.com/Apple-MF839LL-13 ... B00UGBMRQ8
2.7 GHz Dual-Core Intel Core i5 Processor (Turbo Boost up to 3.1 GHz, 3 MB shared L3 cache)
8 GB 1866 MHz DDR3L RAM; 128 GB PCIe-based Flash Storage
13.3-inch IPS Retina Display, 2560-by-1600 resolution
Intel Iris Graphics, Force Touch Trackpad
The one I currently own is a much lower one.
Here are it's specs;
2,53 GHz Intel Core 2 Duo
8 GB RAM 1067 MHz DDR3
NVIDIA GeForce 9600M GT 512 MB
NVIDIA GeForce 9600M 256 MB
(has two video cards / might upgrade this to SSD if you recommend)
Probably the 2015 Macbook Pro will be handling the audio and my old Macbook Pro the visuals (can switch with your recommendation). It's likely that I will load at least 10-15 1920x1080 visuals to Resolume yet will play only 3-4 full lenght and 1-2 one shot visuals simultaneously with 1 or 2 effects on them. My main concern is that would that work safely on either of the laptops? On the benchmark pages I couldn't figure out if those numbers were for visuals playing simultaneously or just total numbers of visuals that can be added to comp without losing FPS.
Also a bonus question is that, the screen they have in a venue is about the size of a cinema screen. I wonder if 1920x1080 visuals would turn to a pixel show in a few meters or should I use 4k definitely?
Thank you very much again - if you can just say, go ahead, buy the 13'' 2015 Macbook Pro and you can safely play 3-4 Full HD videos at the same time on a single screen I will be satisfied enough. Or say stop obviously

Thank you endlessly.