You sure you want a wildfire? If there isn't a specific reason, then you might want to consider the Galaxy S II for $99 (if you want Android) or the Nokia 710 (if you want to try out WP7, available in January). Of course, the $99 is an on contract price, so if the Wildfire is $150 off contract and you do not want to extend yours, then it would be a great deal.
If you're looking at used phones, if you're willing to go a little higher, there are a lot of phones that are much more capable than the Wildfire. For example, the G2 usually goes for $200 on CL.
no, it's not a good phone. it's slow had low memory and cannot be rooted. don't buy thru best buy, go to t-mobile and get one of the better free phones available.
I've never used a Wildfire, but I do know its a lower-spec HTC phones. Personally, even their flashship phones feel a little sluggish since their so bloated with Sense. I can't even imagine using one of their slower phones with Sense. The Wildfire S, to my knowledge, can only be S-OFF/Rooted with an XTC Clip, which is an expensive hardware modification.
For around the same price range, there are quite a few better phones you could snag off CL. As mentioned, the G2 would be a good choice. So would the original Galaxy S / Vibrant. You can also get the Mytouch 4G for around that price if you want to give Sense a whirl on a phone that can do a decent job of running it.
I would want you to change your mind and would highly recommend you to go with samsung galaxy S2...its an awesome android smartphone....i am sure you will love it.And it will make your first experience of a smartphone wonderful.