Add another Palladium hater, here. The system doesn't make a whole lot of sense, and the various numbers in the game do not scale well with each other. So, you could have a rocket that dealt, say, 2d6 mega-damage, and it would have flavour text saying it can easily take out a tank in one hit. Then, you'd see the listing for an average tank having, say, twenty mega-damage. Then, in the same book, you'll see another tank that has 60 mega-damage. And then, also in the same book, there will be an artillery cannon that happens to deal 10d4 megadamage.
Nothing is on the same scale, and that can make things very annoying.
The skill system used to annoy me, but in play, it actually works out fairly well. There are some problems with it (only a high intelligence improves your skill modifier, low stats do not reduce your skills, and the book doesn't detail modifiers for difficult or easy skill checks), but they're decent as a starting point.
Combat in Palladium is awful. Apparently, it works in the basic RPG, but in all of the tacked-on games, it sucks. It really turns into a "He who has the most actions, wins" - and a series of swapping dice rolls until somebody gets lucky. I'm sure Siembieda will step in and explain just how "realistic" it is - I used to cringe reading his rulebooks, when he'd step in and explain just how perfect a rule mechanic was.
(For what it's worth, I can't stand his writing style. I always feel like he's talking down to me!)
Those, by the way, are all problems with the Palladium system in general. ROBOTECH is one of the better ones, and we actually played it for a bit. The problem with it is one that you see in all mech-based RPGs - how to make characters matter when they spend most of their time inside a mech. The numbers in the game are kept comparitively low, making the game work internally - just don't put Robotech mechs into a RIFTS game, or they'll be blown away. As a case in point, I think the SDF-1 in Robotech has half the mega-damage of a Glitter-Boy mech in RIFTS.
the character classes, as I remember them, were fairly interesting, and fit the genre well. Our biggest problem had to do with making your character worthwhile - we were in our mechs so often, that it didn't really seem like our character choices mattered. What made this worse was the fact that there are no rules for repairing your mechs, meaning if you play a mechanic character, there's no real reward for doing so. After all, does a successful repair check mean you've fully repaired your mech, or what? How long does a repair check take? And so on.
In fact, that's the big problem with the game. There's a lot of unexplained information in a game that doesn't have a unified mechanic or anything like that. Meaning, most of the game is in the GM's hands. For some groups, that's a great thing (and I personally think that most ongoing Palladium games are ongoing because the GM is good at what he does), but in general, I think that can be a problem.
Carrying on, we found ourselves playing wildly different characters (I think I was an Ace Pilot, my friend was a mechanic, and we had a Gunner-type character... It was over ten years ago, so I'm hazy on the details)... but we all decided to go for the same mech. And really, most of the mechs seemed pretty similar in capabilities. And if one player chose a different mech, what you'd see would be only one character in the group acting at any one time - the long range guy would fire at will while his companions sat around... then the enemies would get to middle range, and the middle-range mech would have a feel day... and then the enemies would close, and your close range mech would kick butt while the companions did very little.
So, yeah. We played it for a month or so, and then gave up. It wasn't fun for us. At the time, I vastly preferred mechwarrior. Now that I'm not so into the Giant Robot thing, I wouldn't really run either game... but if I had to choose between the two, I'd still go with Mechwarrior (unless the Catalyst Edition has seriously been changed from the 2nd Edition Mechwarrior rules).