I am in need of a new MacBook Pro but I cannot decide on whether I should go for the 13"TB or 15"TB model. This is mainly because I do not know how potent the dual core processors are in the 13" model for the tasks I need to do. I consider myself as a 'professional' user, and under this term I understand someone who actually works with his machine on a daily basis for a living. I work at university and use my Macbook Air on a daily basis for several hours. I prefer using my own macbook instead of going with one of the university’s provided desktop Windows machines, because this way I have all my documents, PDFs and other materials with me all the time. This also means that every day I am carrying my Macbook Air to university, plugging in several devices and an external monitor, carrying it over to lectures etc., plugging it back in, and at the end of the day, unplugging it again taking it home. So far, I have been using a Macbook Air, 13", Mid 2011, 1,7 GHz with 4 GB Ram for roughly 5 years. Today, the system seems somewhat slow for the tasks that I have to do on a daily basis (activity monitor shows me yellow RAM usage, fans really loud under several tasks), and this is why I feel the need to upgrade to a MacBook Pro. I will stick to a Mac, because the MBAir has served me well for the last 5 years and I need impeccable built quality since I’m using this machine for hours every day - no way any Windows laptop would have lasted that long and I see no Windows competitors atm (dislike the XPS "carbon fiber" thing, won’t plug in a Razer Blade with that ridiculous logo in front of my students, surface book’s second version not out yet in Europe). At home, I also have a 3570k @ 4.2 GHz and a Radeon 7950 and a 4K monitor. Obviously, my old Macbook Air cannot output 4k, so I have separate SSD running Hackintosh with that monitor, giving me the performance of , I presume, an iMac. When I am at home, in other words, I mostly use my desktop computer, although it probably drains way more power than a next gen MacBook Pro. Right now, I cannot make up my mind which model I should go for, and it will be probably best to say which things I am doing / need to do with the new Macbook Pro and some further thoughts: I will need to plug in (1) external mouse, (2) external keyboard, (3) external monitor (currently mini-DP adapter), (4) external RJ45 adapter (otherwise I cannot access the university printers). Right now, I am using a Hub that I just plug into one slot of the Macbook Air. I assume that I can just buy one of those 9€ adapters (Usb-C to Usb-A) and plug in my existing Hub - am I right? I plan on (5) plugging in one more monitor. In other words, most of the time I will use the MacBook with an external display. Main tasks / daily usage: For course preparation etc, I am working with / need to run several instances of Word-documents, several instances of Acrobat Pro (several PDFs), several instances of PowerPoint, Excel sometimes, the Mail program, Safari with several tabs, and notes, simultaneously. I need to be able to display two documents next to each other so I can work efficiently. The new MacBook Pro must be able to connect to my 4k monitor at home at 60fps over DP 1.2 with no lag whatsoever. I want to be able to use Lightroom without lag (24MP Raw files) - I know that Lightroom is somewhat sluggish atm for a lack of GPU acceleration while browsing through previews. Sometimes I use Photoshop as well. I cannot really imagine retouching on the macbook pro itself with that trackpad, so probably this will be done on my external 4K monitor and mouse / Wacom graphic tablet. I don’t edit videos (sometimes just playing some 4k videos of my phone). I sometimes want to connect midi devices (Ableton Push + midi keyboards) to the MacBook and run several instances of virtual instruments within Live. The MacBook needs to remain fairly silent - currently my MBAir cannot handle this scenario without getting really hot and the fans going crazy (after all, it is not supposed to handle these 'pro' tasks). Will the 13 inch be sufficient? Any experience by Ableton users with the 13 inch? Can it handle Serum / Diva and some instances of Sylenth? Silence (no audible fan noise) with normal usage. Gaming: It needs to be able to run CS GO at least at 100 fps (bootcamp) - yes I know … boys will be boys. The 460 15 inch can obviously do that, what about the 13 inch? Battery: It will mostly be plugged in (for reference: my MBAir is now 1775 days old and only has 153 loadcycles with 84,6 % of the design capacity left), but it would be nice to being able to charge it with a battery pack: So far I have heard that the 13" models might be powered by a power bank - is it likely that there will be power banks that can charge the 15"? Given the requirements: Is the 13 inch powerful enough for the daily tasks? The only reason why I would go for the 13 inch is because of the portability; if it is powerful enough, however, to do the things mentioned above, I will gladly go with a 13 inch model. On the other hand, the 15" seems to be only slightly larger than my current MBAir. It will be heavier, though (about a small bottle of water). I wonder if this is the right machine for me because I carry it around every day. In case of the 15 inch, I would go with the 460. Both models will have to have 512GB ssd and 16GB Ram, unfortunately the 16GB version never (13 inch) shows as "stock" on the Apple store but seems to be BTO only. Would 8GB be enough? Price difference between 13" with 512 SSD, 16GB and 15" with 512 SSD and 16GB + 460 will be roughly 500 € (for almost double the performance?). The 2015 versions seem to be only slightly cheaper (maybe 200-300 €), and buying a 2 pack of USB-C to USB-A adapter costs 7€. I also see the potential of the Touchbar for Office and Ableton (e.g., in Word quickly changing style sheets, formatting options, displaying definitions etc., controlling VST’s parameters). I plan on using this Laptop for the next 4-5 years. I greatly appreciate any input! Thank you for your time.