Being a lumia 520 user I can say yes, certain apps often give loading or resuming screens after denim, but the whole picture is much glossier. Even high end games run super smooth on my phone, better than android phones with 2 GB RAM . Besides the low resource consuming characteristic of windows has been it's core value. Microsoft may not wish to change these core values, but are forced by the android phone market offering ridiculous specs at cheap prices, hence the 1 GB RAM on even the 435. Leaving out 512 MB devices from the W10 update would not only bring scrutiny from existing fans and users but also put a question mark on the core aspects of windows as an OS which has been its trademark since its inception as a mobile OS for phones from the time of WP 7 which ran smooth with the least of hardware specs. Thoughts guys?