The Homeworld Remastered Collection
...is absolutely worth your time and money.
I'll list some of the pros and cons:
Pro:
* The graphics are utterly beautiful; there's an enormous amount of detail put into the ships, and the effects are top notch. The cutscenes have been updated as well. Even with my fairly low-end laptop, playing with most of the graphics enhancements on didn't significantly affect performance.
* The audio has been overhauled and cleaned up. If it was possible, the music sounds even better than it did 15 years ago, and the voice files and sound effects have been touched up with much higher fidelity.
* The UI has been cleaned up. Not as clunky as it was in HW1.
* Multiplayer and CPU skirmish allows for players to play as any of the HW1 and HW2 races; you can have Kushan vs. Vaygr or Taiidan vs. Hiigaran.
Cons:
* Bugs do exist. Several players on the Steam forums have reported CTD during the singleplayer campaigns, as well as during multiplayer.
* Multiplayer is only in Beta right now.
* Cataclysm wasn't included; only HW1 and HW2.
* The HW2 mechanics were brought into HW1. The same UI, research costs resources, and a general lack of formations. The only thing that doesn't apply to the HW1 races are squadron building; Kushan and Taiidan strikecraft are still built individually, but much much faster than before.
And here are some before and after screenshots:
