Despite the common opinion, HTML::Template::Compiled is not that fast. Even more, it's slow. It's even slower than Template::Toolkit. If you try to use it in your average CGI script, you probably wouldn't see any performance boost, quite contrary. With file cache, it is better than TT, but still loses to plain old HTML::Template.
But if you can actually use memory cache, things change. HTC beats everything. Severely. So, with FastCGI or mod_perl you should stick to HTC beyond doubt.
Also, new features rock. TMPL_ELSIF and TMPL_SWITCH are bliss. Dot-notation saves a lot of typing and makes your code much clearer. That's why I use this module even when it leads to slower code.
I don't think that HTML::Template::Compiled is so good like some people think. It's fast, okay, but I think it's just a imitated Template-Toolkit. --- HTML::Template::Compiled is much better as I thought... Upgrade from 1 star to 4! The 5. star is reserved for stability and fewer changes in further releases.
I have a very favorable first impression of this module. It deviates from HTML::Template's API in a few ways, such as removing die_on_bad_params and adding a dot notation like TT's. I like those changes. I ran the included "bench.pl" script and found that on my system it was repoted to be about 5 times faster than plain HTML::Template, and about 10 times faster than Template Toolkit. (Others have reported that with some tweaks the advantage may be merely 3 times faster under mod_perl).