Bad tasting avocados recently I'm new/ignorant to using avocados and never really enjoyed them until 3 months ago when I bought some on a whim. The avocados actually tasted great. They were creamy and had the consistency of butter. The seed was a bit of a pain to clean, as the skin around the seed would stick to the avocado, so I had to pick it out. Also the avocado skin would tear easily if I were to eat it with a spoon. 

For the past week, the avocados I've been buying taste awful. It feels like I'm eating Aloe Vera or some other type of plant. The avocado is easy to clean (the seed pops out easily) but they taste watery, grassy and bland. It reminded me of why I didn't like avocados. Also they're not mushy/creamy like the previous ones I was buying. In fact, they're hard, even if they seem soft on the outside.

My question is, are these just bad/unripe avocados or are they a totally different type? If so, which are the nice type?
"Watery, grassy and bland" and "not mushy/creamy" (a.k.a hard) match my experience of avocados that aren't sufficiently ripe. An avocado should be very soft and creamy when it's ripe. (But not brown/grey/gross - that's over-ripe.)

At least in Israel, avocados are sold somewhat unripe, since that prolongs their shelf life, and because soft ripe avocados bruise much easier than rock-hard unripe ones. If you buy an avocado that isn't ripe yet, you should wrap it in some newspaper, and leave it out of the fridge until it's ripe. depending on how unripe your avocado is, that can take a week or more.

I'm afraid I don't know the names of American Avocado varieties, but my experience has been exactly the same with the green smooth-skinned elongated ones, small black rough-skinned ones that peel easily, and roundish, leathery-skinned green ones. When ripe, they all taste pretty much the same.