I find that indoor usually tastes better simply because it is fresher but is usually not near as strong as outdoor. I have always gone for the strongest weed with the best taste with strength being the most important.
I am now aware that some folks on this form are actually growing weed that does not get you that high for treating certain ailments. They want the pain relief and other properties of marijuana without the high feeling. If this is what you are looking for then indoor weed will be fine for you. If you want weed that will get you really high then generally you should go for the outdoor.
I have constant back pain that I treat exclusively with marijuana. I find that marijuana is just marginal at actually reducing the pain but allows me to not think about the pain. I use cookies mainly for sleeping at night. I need really strong marijuana. If I have to think about whether I am high or not it is not working.
I use a microscope to verify that every plant I grow is at the same level of maturity before harvesting. This allows me to verify which plants are actually the strongest.
I know that there are a lot of outdoor growers who harvest early due to paranoia, misinformation or greed (cartels) etc. that give outdoor weed a bad name. The same can be said of some indoor growers. The grower can definitley affect the quality of the weed so comparisons can be difficult. Fully mature weed is good whether grown indoor or outdoor. It is just that properly grown outdoor weed will be stronger.
Just my 2 cents.