This subject has been mentioned to death on AK over the past decade. Here we go again:
-Remember, with electrolytics now in 2018, that the counterfeit rate is pushing 50%. Freshness and date of manufacture is everything. Even with good re sellers like Mouser and Digikey who have huge inventories they can not and do not verify every single unit..
-Tier levels are everything now. This article should be a sticky:
https://www.tomshardware.com/reviews/power-supplies-101,4193-5.html
-As already mentioned, always go with poly vs electrolytic if possible.
-Always too much emphasis on exact size. Mod your replacements or chassis and fit the replacements if possible. Insulate the leads with heatshrink if needed unless you have to have exact size snap-ins which is rarely the situation. You can always modify.
-Never and I mean never replace any electrolytic with a tier 3 or 4 brand name from a shady seller. Most consumer electronics all contain tier 3 or 4 lytics from the factory..