RPOL Super Slow?
Can confirm similar issues; got a 502 error message on the responsive site and loading the page for this answer took about 43 seconds, even if the note at the bottom says "generated in 0.072 seconds".
Also, I feel like mentioning that the responsive version of the site (which I've been using almost exclusively for the last month) has been giving me the same problem, in case that might be relevant.