The best choice in Taiwan tends to be the bottom shelf stuff which comes in old school glass bottles and is sold for dirt cheap prices. Take a peek at the ingredients list and compare it to the top shelf stuff which sells for nearly triple the dosage price. You'll quickly notice (with the help of the internet I'm sure) that they are the same. Most folks will tell you "only old people use that", which, while true, is something you should completely ignore.
Cosmed, Watsons, select convenience stores and nearly every pharmacy in Taiwan carry the following two brands. They are the medicine you should take when you're sick with a cold in Taiwan.
友露安 - you lu an - is a personal favorite, if only because every store carries it and the clerks always laugh at you when you buy it. Their standard product comes in a blue bottle, and has everything you need to make those aches and pains go away. If you're coughing buy the powder blue one which is "extra strength" because it has cough medicine. Personal opinion: these two are the best products on the market.
The box this comes in is the same color blue. Same words. Same three umbrellas.
To save you time researching ingredients in the store. A good cold-fixing blend, IMHO.
傷風友 - shang feng you - is another personal favorite, if only because its chemically nearly identical to youlu'an and has two cats on it instead of three umbrellas. It comes in a green box. I've never tried their other products besides the standard blend, but it worked as well as the umbrella brand.
Both of these guys carry some extra caffeine and a higher load of the non-acetaminophen drugs than more of the upmarket stuff. Be careful with the dosing and DONT copy the locals who drink the whole bottle down in one go. Terrible, terrible idea. The recommended dose is to drink 8ml four times a day but that might be a bit weak for some people.
A few disclaimers before we wrap up:
This is an unpaid/uninfluenced review written about personal experiences and doesn't come from a doctor. Follow all dosing guidelines on the bottle, and ask a pharmacist - many of whom speak English beautifully - if you have any concerns. Consult a doctor when needed, because they're actually very helpful professionals.